Exercises for Older Adults

Exercise for Both Endurance AND Intensity

  July 20, 2021    

For maximum health benefits, you should work for both endurance and intensity in your exercise program. We have lots of evidence that exercise prolongs lives by reducing risks for chronic diseases such as high blood pressure, heart attacks and diabetes (PLoS Medicine, January 12, 2021), and adding intensity to a workout increases its health benefits (Brit Med J, Oct 7, 2020;371).

A recent study from the University of Guelph in Ontario, Canada suggests that you will gain more health benefits by trying to exercise intensely on some days and doing slower recovery exercise on the other days (Med Sci Sports Exerc, June 2021;53(6):1194-1205). In this study, 23 overweight participants were divided into two groups that exercised on stationary bicycles for six weeks:
• Endurance Group: Five days a week, 30–40 minutes of continuous exercise at about 60 percent of maximal effort
• Intense Intervals Group: Three days a week, 4-6 intervals with each lasting for 30 seconds at almost all-out intensity, with a two-minute recovery between each intervalS

The researchers found that both the endurance group and the intense intervals group had increased heart-lung fitness and ability to control blood sugar levels after eating a meal, but only the endurance group had lower blood pressure, decreased body fat, and ability to control blood fat levels after eating a high-fat meal. This shows us that short bouts of intense exercise alone are not enough; your exercise program should include both some endurance work (time and distance in your activity) and some short bursts of intensity (increased effort).

Stress and Recover
I recommend that exercisers at all levels should follow a stress and recovery exercise program. Competitive athletes need to exercise every day to gain maximum strength, and they know that they have to exercise intensely to improve in their sport. They quickly learn that exercising intensely damages muscles to cause delayed onset muscle soreness (DOMS) and they need to follow each intense workout with less intense recovery workouts.

You will become more fit by taking a hard workout and then going at low intensity for a day or two than you will by exercising at the same leisurely pace every day. You have to damage muscles to gain strength and enlarge muscles. Every muscle is made up of thousands of fibers like a rope is made of many strands. Every fiber is made up of blocks called sarcomeres that fit end to end like a row of bricks. Sarcomeres butt upon each other, end-to-end, at Z-lines (Diagram). Muscles contract only at each Z-line. When you exercise vigorously, you damage these Z-lines and when they heal, the muscle fibers are stronger, so all knowledgeable athletes take some intense workouts to damage their muscles at the Z-lines. On the next day their muscles are sore and damaged and they exercise at a relaxed pace. When the muscles are healed and the soreness lessens, they take their next intense workout. If athletes exercise at low intensity during the healing phase of the Z-lines, their muscle fibers will become stronger than if they rest. If they exercise vigorously when their muscles are sore, they are likely to tear them and become injured.

Non-Athletes Also Should Exercise Every Day
Forty percent of North Americans die of heart attacks. One of the most common causes of the arterial damage that precedes heart attacks is a high rise in blood sugar after meals. Resting muscles remove no sugar from the bloodstream, but contracting muscles remove sugar rapidly from the bloodstream without even needing insulin. This effect is strongest during exercise and diminishes to no benefit about 17 hours after you finish exercising. If you want to use exercise to help control blood sugar, you need to do it every day.

An Exercise Program for Everyone
CAUTION: Because a person with blocked arteries leading to the heart could suffer a heart attack during exercise, please check with your doctor before starting a new exercise program or increasing the intensity of your existing program. Whatever activity you choose, try to exercise every day. If you are just starting out, spend about six weeks at a slow pace until you are comfortable in your activity for thirty minutes or more. Then you are ready to alternate more intense days with easier workouts.

Intense Days: Stress refers to intensity, not the length of your workout. You can gauge the severity of the stress by how hard you breathe and by the amount of burning you feel in your muscles during exercise. Interval training means that you start out slowly, pick up the pace, slow down immediately when your muscles start to burn, recover by going very slowly for as long as you want, and then pick up the pace again.
• On your hard days, warm up by going very slowly for five to 10 minutes. Going slowly at the start of a workout warms up muscles to help make them resistant to injury. If your muscles still feel tired or heavy, do not try interval training. Exercising with tired or sore muscles can cause serious injuries.
• After you warm up, pick up the pace gradually until you feel burning in your muscles and immediately slow down. Then go at a very slow pace until the soreness goes away, your breathing returns to normal and you feel recovered. How long it takes to recover is irrelevant. You take your next faster pick up when you feel that you have recovered, not from any preset time. Then pick up the pace until you feel burning again.
• If you are not planning to compete, you do not ever need to go at 100 percent intensity. People who are just starting to do interval workouts should pick up the pace only slightly and not become short of breath. Slow down and get out of the burn as soon as you feel it. As soon as the burning and fatigue go away, and you are not breathing hard, try to pick up the pace again. In early workouts, you may only be able to do one hard pickup. Do not start your next pick up until your legs feel fresh. As soon as your legs start to feel heavy, stop the workout. Trying to increase the pace when your muscles feel sore, or trying to work through heavy or tired muslces invites injury.

Easy Days: The day after your hard workout, your muscles will probably feel sore and you should take an easy workout. If the discomfort does not go away after you warm up, is worse on one side of your body, or increases as you exercise, stop exercising immediately and cool down. You could be injured and continuing to exercise will delay healing. If you feel better as you exercise casually, continue to exercise until you feel any discomfort or heaviness. Always stop every workout when your muscles hurt or feel heavy. Keep on taking easy days where you exercise at low intensity until you feel fresh again.

My Recommendations
I believe that every healthy person should try to exercise every day. You will gain a much higher level of fitness by “stressing and recovering.” Exercise more intensely on one day and go slowly on the next day or days. Only when your muscles feel fresh should you try to pick up the pace again.

JULY 12

High Blood Sugar After Meals Predicts Heart Attacks

  August 1, 2020  4018  

A review of 129 studies found that tests for a high rise in blood sugar after meals were better than tests of fasting blood sugar levels as a predictor of coronary heart disease, strokes, or death from any cause (British Medical J, July 17, 2020;370:m2297). Having a blood sugar greater than 155 mg/dL one hour after you eat a meal markedly increases your risk for heart attacks, strokes and premature death, even if your fasting blood sugar is normal (Atherosclerosis, Nov 17, 2016;256:15-20). This test is more dependable than HBA1c, the test used by most doctors to diagnose diabetes today (J Clin Endo & Metab, Nov 15, 2018).

More than 30 percent of type II diabetics don’t know that they have diabetes because their fasting blood sugar is normal at less than 100 mg/dL, so their doctor has told them that they are not diabetic. People who have fasting blood sugar levels between 100 and 125 mg/dL are often told that they have “pre-diabetes,” when they are already at very high risk for heart attacks (BMJ,2016;355:i5953). More than seventy percent of people with pre-diabetes eventually develop diabetes (Diabetes Care, 2020;43(Suppl 1):S32-

In my opinion, use of the term “pre-diabetes” is going to kill a lot of people because extensive damage is done to every cell in your body when your blood sugar rises too high after meals, even if your fasting blood sugar level is normal. I believe that you should be told that you are already diabetic and at high risk for all the side effects of diabetes if your blood sugar rises above 155 mg/dl one hour after you eat a meal. Most cases of type II diabetes are caused by inability to respond adequately to insulin, which can be cured with lifestyle changes but not with drugs.

Who Needs to Be Checked for One-Hour-After-Eating Blood Sugar?
People who have any of the following factors should get a blood test for blood sugar one hour after they eat a full meal:
• excess fat (body mass index greater than 25)
• increased belly fat (pinch more than 2 inches of fat underneath your skin near your belly button
• waist circumference in men > 37 inches (94 cm), in women >31 inches (80 cm)
• proportionately small buttocks (an independent risk factor for diabetes)
• smokes or lives with a smoker
• systolic blood pressure >120 at bedtime
• diastolic blood pressure > 90 at bedtime
• high bad cholesterol: LDL >100
• low good cholesterol: HDL <40
• Lp(a), a clotting factor, >30 mg/dL
• C-reactive protein >3 mg/L
• high sensitivity CRP >10 mg/L
• HBA1c >5.6

My Recommendations
Type II diabetes puts you at increased risk for heart attacks, strokes and premature death. Many people do not realize that they are diabetic because their doctors have told them incorrectly that a fasting blood sugar below 100 mg/dL rules out diabetes. Check the risk factors listed above. As part of your yearly check-up, I believe that everyone should get a blood sugar level drawn one hour after they eat a full meal. If it is greater than 155 mg/dL, make immediate lifestyle changes to reverse the damage that has already occurred from high blood sugar and to prevent further damage. We have no drugs that cure diabetes, but most type II diabetes can be prevented or cured with lifestyle changes:
• lose excess weight if overweight
• exercise
• avoid smoking
• avoid or severely restrict alcohol
• eat a healthful diet with plenty of vegetables, fruits, whole grains, beans, nuts and other seeds
• avoid sugared drinks including fruit juices, sugar-added foods and other refined carbohydrates, red meat, processed meats, and fried foods
• keep hydroxy vitamin D levels above 30 ng/mL
See Most Type II Diabetics Could Be Cured with Lifestyle Changes
How Exercise Helps to Prevent Diabetes and Heart Attacks

July 12

Blood Pressure Guidelines

The American Heart Association, the American College of Cardiology and nine other heart health groups agree that you have high blood pressure if your blood pressure is above 130/80, not 140/90 as the previous guidelines recommended (American Heart Association’s annual meeting, November 13, 2017). This means that 46 percent of North American adults now have high blood pressure which means that they are at increased risk for heart attacks, strokes, diabetes and premature death. The new guidelines will triple the number of men under 45 years of age with high blood pressure, and double the number of women under 45 with high blood pressure. Another 40 percent of the population will develop high blood pressure as they grow older.

The blockbuster SPRINT study of almost 10,000 people showed that blood pressures above 130 increase risk for death (N Engl J Med, Nov 26, 2015;373:2103-2116). High blood pressure causes heart attacks, strokes, and kidney disease and puts you at increased risk for developing dementia in later life. High blood pressure is intimately associated with high blood sugar levels after meals, and high blood pressure is one of the criteria for diagnosing diabetes.

Lowering Blood Pressure without Drugs

The majority of people with blood pressures between 120 and 140 have the potential to lower their high blood pressures without taking drugs. If they are sufficiently motivated, they can get their blood pressures to normal with lifestyle changes:

• getting rid of their excess belly fat

• losing excess weight

• exercising daily and growing larger muscles

• avoiding alcohol and smoke

• eating a high-plant diet with lots of vegetables, fruits, whole grains, beans, nuts and other seeds

• limiting or avoiding sugar-added foods and drinks, meat from mammals, processed meats and fried foods

• limiting salt intake

• drinking only water, coffee or tea, with nothing added to them

• keeping blood levels of hydroxy vitamin D above 30 ng/mL

Losing just 10 pounds can reduce systolic high blood pressure by 5 mm of mercury.

Most people who cannot get their systolic blood pressures below 130 with these lifestyle changes will probably be advised to take drugs.

Checking Your Own Blood Pressure

Never let your doctor use a single blood pressure measurement to diagnose high blood pressure. Your blood pressure can rise just because you are in the doctor’s office. It can also rise when you eat, exercise or move around, or when you are startled or afraid. I recommend that everyone should have their own arm blood pressure cuff (wrist cuffs are not very dependable). They are inexpensive and are available at any pharmacy. Every night for at least a week, take your blood pressure when you are ready to go to bed and have been resting for 10-15 minutes. That is when your blood pressure is usually lowest. Keep a record of the readings and take the average after a week. If your systolic blood pressure averages greater than 120, you have high blood pressure and need serious lifestyle changes immediately. Check with your doctor.

Who Should Take Drugs for High Blood Pressure?

People who have high blood pressure plus two or more of heart attack risk factors listed below will probably be advised to take blood-pressure-lowering drugs. Your doctor can examine you and order all of these tests:

• LDL (bad) cholesterol>100

• HBA1C>5.7 (diabetes)

• CRP>1 (inflammation)

• Abdominal obesity

• Small hips

• Resting heart rate >70

• Lp(a)>125 (blood test for a genetic disorder)

• Triglycerides >150 (primarily from dietary sugar)

• HDL (good) cholesterol<40

• Homocysteine>10 (genetic or vitamin deficiency)

• Small LDL particle size (an indicator of diabetes)

• Family history of heart attacks

See my report on Heart Attack Prevention

July 2

Runner’s Heart: The Consequences of Competitive Exercise

Medical researchers agree that exercising from the early years into old age helps to prevent heart attacks, strokes and cancers, but this month a study from The University of Manchester showed that long-term intense training for racing in animals can damage the atrial-ventricular node that regulates the frequency of heart beats to cause heart block (Circulation Research, 2021;129:e1–e20). “Heart block” means that the electrical signals that control your heartbeat are partially or completely blocked as they move from the top chambers of your heart (atria) to the bottom chambers (ventricles).

A training-induced heart block in human athletes is usually harmless and reversible when the athlete stops exercising (Dtsch Arztebl Int, Jan 7, 2013;110(1-2):14–24), but sometimes, such as when competing all-out in endurance sports, heart block is associated with increased risk for atrial fibrillation (J Am Coll Cardiol EP, Sept 2017;3(9):921–928). For example, an 80-year-old non-smoking, non-drinking life-long competitive marathon runner, with a resting heart rate of 40 beats per minute, fell while running and died from a blood clot thrown from his heart to his brain, caused by atrial fibrillation (Am J Case Rep, May 26, 2020;21:e924580). An irregular heartbeat induced by training and racing to an athlete’s limits can be detected by laboratory tests and in rare cases, may be an indication for the athlete to have an implanted heart pacemaker.

The Difference Between Racing and Just Exercising
Competing in endurance sports often requires exercising through pain and discomfort. Contracting skeletal muscles send large amounts of blood back to the heart, which stretches the heart muscle to cause it to beat faster and with greater force (Starling’s Law). When you are just exercising and feel some discomfort, you usually reduce the intensity of your workout to get back into your comfort zone. On the other hand, when you are competing in an endurance event, you try to push yourself through pain and discomfort, which can stretch the heart muscle fibers to near their limits.
• This stretching of the heart muscle can cause damage to the muscle filaments that increases stimulation of the vagus nerve that regulates heart rate, which can cause a slow heart rate (bradycardia) that can sometimes cause atrial fibrillation.
• Atrial fibrillation means that the atrium, the upper part of the heart, starts to flutter instead of contracting before the bottom part of the heart contracts. This allows blood to collect and stop moving in the upper part of the heart, which increases risk for forming clots that can pass to the brain to cause a stroke.

My Racing History
I had to work all through high school, college and medical school, so I never trained seriously for racing until I was in a fellowship at Johns Hopkins in 1963 at age 29. I worked up to running three times a day and competed seriously in races until 1974 at age 39. I trained so hard that I became an expert on running injuries because I had experienced many of them myself. Eventually I found that bicycling was much less likely to injure me, so from age 55 onward, I have tried to ride a bicycle seven days a week and now at age 86, average 150 miles each week. I have never raced on a bike, but I ride hard for about 30 miles on Tuesdays, Thursdays and Saturdays and around 15 miles very slowly on the other four recovery days.

This week I have been saddened by the deaths of two of my running contemporaries: 
• Ron Hill, who died on May 23, 2021 at age 82 of dementia and an overwhelming urinary tract infection. He ran every day for 52 years and had a marathon best time of 2:09:28. In 1968, he set the world record for 10 miles twice (46:44.0); in 1969, he won the European marathon championship; in 1970, he set the Boston Marathon record (2:10:30) and won the Commonwealth Games marathon in a European, British, and Games record of 2:09:28 (Runners’ World, May 4, 2021).
• Dr. Joan Ullyot, who died on June 18, 2021 in Aspen, Colorado at age 80 of a heart attack. She was a pioneer in women’s long-distance running who did not run until she was 30 years old and ran her first marathon in 1974 at age 33. She won the master’s section of the Boston Marathon at age 43 (2:54:17), won 10 women’s marathons, and at age 48 ran the marathon in a women’s masters record 2:47:39. She also wrote and lectured extensively and had several best-selling books on women running in marathons (Runner’s World, June 23, 2021).

As You Age, Balance Intense Exercise with Common Sense
The American Heart Association cites more than 300 scientific articles showing that exercising excessively long and intensely may be associated with heart damage, increased plaque formation in arteries, scarring in the heart itself, markers of heart damage in the bloodstream, or atrial fibrillation (Circulation, Feb 26, 2020). However, a review of 48 articles found no reduction in lifespan, no matter how much a person exercises (Br J Sports Med, Aug 12, 2019).
Can Intense Exercise Increase Your Risk for a Heart Attack?
Vigorous Exercise Won’t Hurt a Healthy Heart

People who suddenly increase the length and intensity of their training may be at increased risk for heart attacks during exercise. This includes people who are starting a new exercise program, or regular exercisers who decide to enter an endurance event such as a marathon or triathlon so they suddenly increase the intensity and duration of their training (Circulation, Feb 26, 2020). CAUTION: Before increasing the intensity of your exercise program, check with your doctor to see if you have any pre-existing conditions such as heart arteries blocked by plaques, or heart or blood vessel abnormalities.

My Recommendations
I believe that with few exceptions, virtually everyone should try to exercise every day. Older athletes can continue to compete into their later years, but they need to remember that preventing heart problems involves more than just exercising. You can help to prevent heart attacks, cancers, dementia and premature death by following an anti-inflammatory lifestyle:
• Eat a plant-based diet that includes lots of fruits, vegetables, whole grains, nuts, beans and other seeds
• Avoid or severely restrict sugared drinks, sugar-added foods, red meat, processed meats and fried foods
• Lose excess weight if overweight
• Keep hydroxy vitamin D levels above 30 ng/mL
• And of course, exercise regularly

JUNE 29

Muscle Loss from Inactivity: 34 Percent in Just Two Weeks

A study from the University of Copenhagen showed that wearing an immobilizing knee brace for just two weeks caused men in their 20s to lose 22 to 34 percent of their leg muscle strength, while men in their 60s lost 20 to 26 percent (Journal of Rehabilitation Medicine, June 26, 2015).

It took them six weeks of exercising on a bicycle 3-4 times a week to restore the leg muscle size and ability to exercise, but even that did not fully restore the leg muscle strength. This study shows that:

• When muscles of young men are immobilized for two weeks, they lose strength equivalent to aging 40 or 50 years.

• As soon as you stop moving, your muscles start to weaken.

• The larger your muscles, the more muscle you have to lose.

• Younger and stronger people may lose strength even faster than older people.

Other studies show that it takes three times the amount of time you were inactive to regain the muscle size that you have lost, probably because you were immobilized 24 hours a day and you exercise for only a short time each day.

Aging Weakens Muscles Even if You Exercise

Inactivity at any age causes muscles to weaken, and you are likely to lose muscle strength with aging no matter how much you exercise. Every muscle in your body is made up of thousands of muscle fibers just as a rope is made up of many strands. Every muscle fiber is innervated by a single nerve fiber. With aging you lose nerves, and when you lose a nerve attached to a muscle fiber, that muscle fiber is lost also. A 20-year-old person may have 800,000 muscle fibers in the vastus lateralis muscle in the front of his upper leg, but by age 60, that muscle would have only about 250,000 fibers. For a 60-year-old to have the same strength as a 20-year-old, the average muscle fiber needs to be three times as strong as the 20-year-old’s muscle fibers. You cannot stop this loss of the number of muscle fibers with aging, but you certainly can enlarge each muscle fiber and slow down the loss of strength by exercising muscles against progressive resistance using strength-training machines or by lifting weights (Experimental Gerontology, August 13, 2013).

How to Strengthen Muscles

To enlarge and strengthen muscles, you need to exercise them against resistance forceful enough to damage the muscle fibers. You will know that you have done this because you will feel a burning in the stressed muscle during the later lifts and on the next day, your muscles will feel sore. Then you lift lighter weights, or engage in other sports, for as many days as it takes for your muscles to heal. You can tell this has happened when the soreness goes away.

My Recommendations

We are all likely to have some enforced periods of inactivity, but if you realize how quickly you lose muscle strength and how much longer it takes to gain it back, you will avoid voluntary inactivity as much as possible. For example, when you plan a vacation, make sure it involves physical activity that is at least equal to your regular exercise program.

As you age, expect to become weaker and more likely to fall and break your bones. To enlarge muscles and slow the natural loss of strength with aging, you should lift weights a few times in a row or lighter weight many times in a row. You can become quite strong by using 10 to 15 strength-training machines (for different muscle groups) three times a week. Do two or three sets of 10 repetitions on each machine. Always stop immediately if you feel any pain, tearing or excessive burning. See Making Muscles Stronger.

Caution: Check with your doctor before starting a new exercise program or changing the intensity of your existing program.

June 21

Dementia May Be Preventable

The American Heart Association has published a scientific statement on “Harnessing Healthy Behaviors to Prevent Dementia” (Stroke, Mar 15, 2021:52(6A);52:e295-e308). They report that dementia is associated with the following modifiable risk factors: depression, all heart attack risk factors, high blood pressure, diabetes, obesity, high cholesterol, physical inactivity, an inflammatory diet, smoking, social isolation, excessive alcohol use, sleep disorders and hearing loss. Changing these lifestyle risk factors can reduce your chances of suffering from dementia.

Studies presented at the Alzheimer’s Association International Conference in 2019 found that specific healthful lifestyle changes can reduce dementia risk (JAMA, published online July 14, 2019), and that even if you have high genetic risk for Alzheimer’s disease, a healthful lifestyle can reduce your chances of developing dementia (Neurology, published online July 10, 2019). This is very encouraging news, since just about every lifestyle risk factor for suffering a heart attack is also a risk factor for dementia (Alzheimer’s & Dementia, May 12, 2018), and we already have extensive data to show that healthful lifestyle factors help to prevent and treat heart disease.

Dementia means loss of brain function, and your chances of being affected increase with age (Neurology,2013;80(19):1778-83):
• 3 percent of those aged 65-74
• 17 percent of those aged 75-84
• 32 percent of those aged 85 or older

Doctors can predict your risk for developing dementia by ordering an MRI which can show decreased volume of grey matter in the brain (Brain Imaging and Behavior, May 9, 2018). Grey matter is where the brain processes speech, hearing, feelings, seeing, and memory. Having low levels of the good HDL cholesterol increases risk for losing brain tissue and developing dementia 20 years later (Brain Imaging and Behavior, September 26, 2018).

More Studies on Lifestyle to Reduce Risk for Dementia
A study from Rush University Medical Center in Chicago (Neurology, published online July 10, 2019) followed 2,765 individuals for 10 years and found that older people can reduce their risk for dementia by as much as 60 percent by:
• actively using the brain every day, by writing, playing chess, doing crossword puzzles and so forth
• eating a healthful diet
• avoiding smoke
• avoiding or severely restricting alcohol
• exercising regularly
Their healthful diet consisted mostly of vegetables, nuts, berries, beans, whole grains, seafood, poultry and olive oil, and avoided red meat and processed meats, butter, cheese, pastries, sweets and fried foods. Their exercise program consisted of at least 150 minutes a week of biking, walking, swimming, gardening, yard work or similar activities.

Another study, from Exeter Medical School in England, found that people at high genetic risk for dementia who followed a healthful lifestyle for six years had a 32 percent reduction in developing dementia (JAMA, published online July 14, 2019). Studies presented at the same meeting showed that smoking and excessive drinking increase dementia risk. Other studies found that:
• Regular exercisers have much higher brain function in later life, and exercising in your teens correlates with higher memory scores in later life (Age and Ageing, Mar 1, 2019;48(2):241-246).
• A long-term diet high in vegetables and fruit in middle and late adulthood was associated with less memory loss in men (Neurology, Jan 1, 2019;92(1):e63-e75).
• Being overweight and carrying extra belly fat was associated with dementia and brain shrinkage (Neurology, Jan 9, 2019).

My Recommendations
You may be able to prevent or at least to delay Alzheimer’s disease and other forms of dementia with healthful lifestyle habits, such as:
• exercising regularly
• eating a healthful, plant-based diet
• avoiding alcohol and smoking
• exercising your brain with any activity that requires thinking
• avoiding overweight
• avoiding or controlling high blood pressure, high cholesterol and high blood sugar
See Aging and Risk for Dementia

Note: In this month’s radio show on WRTA in Altoona PA, I discussed the newly approved drug for Alzheimer’s disease patients (aducanumab, brand name Aduhelm) and many other topics. You can listen here:
https://www.lightnercommunications.com/episode/podcast-dr-gabe-mirkin-june-2021-wrtas-the-11th-hour-with-doug-herendeen/

June 16

Exercise for Endurance AND Strength

If you want to gain maximum benefit from your exercise program, you should try to do both endurance (heart-lung) activities and resistance (muscle strength) training. The usual way to do this is to:

• do your endurance training with an activity that uses primarily your legs, such as running, walking or cycling

• use weight-training machines aimed at strengthening primarily your upper body and core (belly and back).

If your main sport does not focus on your legs, you will want to do some resistance work for leg strength as well.

How to Combine Strength and Endurance Training

Researchers in Australia showed that adding a weight lifting program to cycling or running will help to improve performance only if you know that when your muscles are sore, you have to take the day off or go slow and easy (Sports Medicine, July 2017;1–14).

• After running or cycling very intensely, you need to go slow and easy for more than 24 hours.

• After lifting weights intensely, you should go easy on those muscle groups for several days

If you want to train the same muscle groups for both endurance and strength, you need to use long recovery periods of less intense exercise after each intense workout, or you will be at high risk for injuries and an over-training syndrome of chronic fatigue and muscle damage. You should not exercise at a fast pace or lift heavy weights when your muscles are still sore from a previous workout.  High-intensity interval cycling done after heavy-resistance exercise decreased strength gains because of the soreness it caused (Scand J Med Sci Sports, Sept 23, 2016).

You can set up a schedule for lifting weights every second or third day and alternate running or cycling intensely on one day and easy on the next, but always listen to your body and back off if your muscles hurt. One study showed that in just six days of training the same muscles intensely, your muscles will be so sore that you won’t be able to exercise intensely and you will have a significant decrease in strength (Research Quarterly for Exercise and Sport, Aug 2015;86(4):387-396).

If you are an athlete who competes in total body endurance sports such as rowing, cross country skiing or swimming,  you should do your resistance training on the same day that you take an intense workout.  Then you may need two or three days for recovery.  Cross country skiers and rowers have the highest rates of fitness and modern runners and cyclists are now  following their training methods, with more than 87 percent of their workouts being recovery and about 10 percent being very intense.

My Program (84-Year-Old Man)

• Strength Training: I try to go to the gym three times a week and use the upper-body weight machines. I do only one set with a comfortable weight until my muscles start to fatigue. On most of the machines I do 20 to 100 repetitions. This type of training does not give me large muscles, but it does help me to maintain strength and avoid injuries.

• Endurance: On Tuesdays, Thursdays, and Saturdays, I cycle 25 to 30 miles on a recumbent tandem with Diana in our tandem bicycle group. We do not go flat out but we do pick up the pace at the end of each ride. On the other four days, I attempt to do intervals on my upright single bike. My legs usually feel stiff in the morning. If they do not recover after a 5 to 10-minute warm-up, I either ride 10 to 13 miles at around 11mph or take the day off completely. I usually have to ride slowly two or three times a week because of muscle soreness.

My interval workouts are done fast enough to make me short of breath, but they are not done at my maximum effort. I do 50 half-pedal strokes at about 80 percent of my maximal heart rate.  Each interval takes 24 seconds and I go about 400 yards.  I do not start my next interval until I feel that I have recovered completely from my previous interval. I stop my workout when my legs do not recover a few seconds after I finish an interval. I usually do between 21 to 24 repeat intervals. See Short Intervals are Best

Caution: Intense exercise can cause a heart attack in a person who has blocked arteries or heart damage. Check with your doctor before you start a new exercise program or increase the intensity of your existing program

JUNE 2

Walk Faster, Live Longer

Paul T. Williams, a statistician at Lawrence Berkeley National Laboratory, has followed almost 40,000 men and women who walk for exercise for more than 10 years. His latest report shows that the faster you walk, the longer you live (PLoS One, December 2013). Picking up the pace is more healthful than just walking slowly, even if you go longer than the recommended 30 minutes per day. In his study group, those who walked at a very slow pace (24 minutes per mile) were 44 percent more likely to die in 10 years than those who walked at a faster pace.

Six years ago, the same author showed that among older runners, the faster runners had healthier medical profiles. They had lower blood pressure, lower cholesterol and lower blood sugar levels (Medicine and Science in Sports and Exercise, October 2008).

Intervals: The Best Way to Increase Intensity

The most efficient way to increase intensity and feel less stress on your muscles is to use interval training. When you exercise, pick up the pace for a short period. As you start to feel burning or fatigue in your muscles, slow down. When the burning and fatigue are gone, pick up the pace. When you feel the burning again, slow down. Alternate these pickups and recoveries until your muscles start to feel stiff and then quit for the day.

Intervals Better than Continuous Pace Exercise

Norwegian researchers showed that high intensity interval training improves every conceivable measure of heart function and heart strength and also helps to prevent both the pre-diabetic metabolic syndrome and the heart damage it causes (Exercise and Sports Sciences Reviews, July 2009). Controlled interval training is now a treatment for heart failure. High-intensity interval training:

• raises the good HDL cholesterol far more than less intense exercise does (Journal of Strength and Conditioning Research, March 2009).

• enlarges telomeres, the end caps that protect your chromosomes. The size of your telomeres predicts how long you will live (Proceedings of the National Academy of Sciences USA, Jan 2012).

• increases both the number and size of mitochondria. The larger and more mitochondria, the longer you can expect to live.

• increases VO2max, the maximum amount of oxygen that your body can take in and use. VO2max can be used to predict your likelihood to suffer a heart attack (Med Sci Sports Exerc, November 2011;43(11):2024-30).

Calculate your VO2max

• makes your cells more sensitive to insulin, which in turn helps to prevent diabetes, heart attacks, obesity and certain cancers.

Interval Training Takes Less Time for Greater Health Benefits

To be competitive, all athletes must train very intensely some of the time. Interval training on a bike can provide you with all the health and fitness benefits of exercising less intensely for a much longer period of time (The Journal of Physiology, March 2010). In this study, subjects used a stationary bicycle to do ten one-minute sprints with a one-minute rest between each at 95 percent of their maximal heart rate, three times a week. This takes less effort than an all-out sprint at close to 100 percent of maximal heart rate. The study supports other research that shows that high-intensity interval training improves all the measures of fitness far more than continuous, less intense exercise. The same authors showed that a similar short workout of all-out sprinting at maximal heart rate took about 90 minutes per week (three workouts of 30 minutes each) and was as effective in achieving fitness and health benefits as many hours of exercising at a much more leisurely pace (The Journal of Physiology, September 2006).

More Benefits from Intense Exercise

Intense exercise for older people is still a controversial subject, but it is far more effective than casual exercise in preventing and treating diabetes (Circulation, July 2008) and reducing belly fat (Medicine & Science in Sports & Exercise, November 2008); Vigorous exercise protects obese people from heart attacks and prolongs their lives, even if they don’t lose weight (Medicine and Science in Sports and Exercise, October 2006); Intense exercise is more effective in preventing heart attacks than less intense exercise done more frequently (MSSE, July 1997); Death rate from cardiovascular disease is lowered by high intensity activities such as jogging, swimming, hiking, tennis and climbing stairs, but not by lower intensity activities such as walking, bowling, sailing, golf and dancing (Heart, May 2003).

What Does This Mean for You?

Since exercise can cause heart attacks in people who already have blocked arteries leading to their hearts, you may want to check first with your doctor. If you are not a regular exerciser, start out very slowly and jog, cycle or do your chosen exercise at a very low intensity each day until you feel the least fatigue in your muscles and then stop. If your muscles feel stiff when you start to exercise, take the day off. In six weeks, most people can work up to a half hour a day of very slow exercise.

You are now ready to start training. Your new workouts will start as your old ones did. Start out very slowly. After five or more minutes, you should be warmed up and ready to start training. Pick up the pace for a few seconds and slow down as soon as you start to feel short of breath or burning in your muscles. Go slowly for as long as it takes to recover your breath and for your muscle to feel fresh again. Then pick up the pace again. Alternate these pickups and recoveries until your muscles start to feel tight and then stop for the day. If your muscles feel tight at the start of a workout, take that day off. Tight muscles mean that your muscles have not recovered from a previous workout. You are now training like a real athlete.

MAY 25

Reduce Inflammation and Clotting to Prevent Heart Attacks

Heart attacks and strokes cause 50 percent of the deaths in North America today, yet many people are not adopting the lifestyle changes needed to prevent the factors that cause them: inflammation and clotting. A new study from the University of Michigan shows how important inflammation is as a cause of heart attacks and strokes (JCI, May 28, 2019). In this study, when mice formed clots in their blood vessels, they also had a rise in blood levels of interleukin-1 beta, a cytokine molecule that causes inflammation. Giving the mice an enzyme called CD39, which blocks inflammation by markedly reducing interleukin-1 beta, reduced the size and number of clots that formed in their bodies. Blocking the anti-inflammatory CD39 increased the number and size of clots.

CD39 is an enzyme found on the surface of white blood cells and the inner lining of blood vessels that inhibits inflammation. It is produced by humans, but its use in humans has not yet been tested and it is not an available treatment at this time.

What is Inflammation?

Your immune system is supposed to protect you. When you get an infection, your immune system produces white blood cells and chemicals that attack and kill germs. When you damage tissue, your immune system produces exactly the same white blood cells and chemicals and uses them to heal damaged tissue. As soon as your tissue is healed or the infection is gone, your immune system is supposed to dampen down. However, if your immune system stays on all the time, it can attack your healthy tissue in the same way that it attacks invading germs or injuries. This is called inflammation.

Many studies show that inflammation (an overactive immune system) can cause the clots that cause heart attacks and strokes. Heart attacks are not caused by narrowed arteries. Heart attacks are caused by a plaque breaking off from an artery, followed by bleeding and clotting. Then the clot extends to completely block blood flow to a part of the heart muscle. Inflammation, which is supposed to punch holes in the membranes of attacking germs, also punches holes in the inner linings of arteries to cause plaques to form and then knocks off plaques to cause the bleeding and clotting that leads to a heart attack.

Reducing Inflammation with Lifestyle Changes

Exercise: Exercising muscles help to control after-meal blood sugar rises that damage tissues to cause inflammation. An extensive review of studies shows that exercise can reduce inflammation even more than statins do (Clin Chim Acta, Jun 3, 2010;411(0):785–793).

Weight Loss: Excess fat, particularly in your liver, causes inflammation, and having markers of inflammation can predict future weight gain (Diabetes, 2003 Aug; 52(8): 2097-2101). Apparently healthy people who have elevated blood markers of inflammation are at high risk for developing insulin resistance and diabetes (Circulation, Jul 4, 2000;102(1):42-7) and gaining fat that, by itself, increases inflammation (J Clin Invest, 2005;115(5):1111–1119). I recommend intermittent fasting for weight loss and weight control.

Avoid Toxins: Toxic substances damage cells to cause inflammation, so you should avoid or limit as much as possible your exposure to smoke, alcohol, recreational drugs or unnecessary prescription drugs, industrial chemicals, pollutants and so forth.

Treat Chronic Infections: Having any chronic infection turns on your immune system to cause inflammation (J Clin Invest, May 2, 2005;115(5):1111–1119), so identifying and treating chronic infections should be part of an anti-inflammatory lifestyle.

Anti-Inflammatory Diet: The food that you eat can turn on or turn off your immune system. See Anti-Inflammatory and Pro-Inflammatory Foods. All fruits, vegetables, nuts, whole grains, beans and other seeds contain soluble fiber that is converted to Short Chain Fatty Acids (SCFAs) in your colon. SCFAs dampen down inflammation, and lower high blood pressure and cholesterol.

Drugs to Reduce Inflammation and Clots

We have many studies that show that inflammation can cause clotting and heart attacks in people who have low and normal blood levels of cholesterol. Doctors regularly prescribe anti-clotting drugs to treat or prevent clotting, but statins are often the only drugs they prescribe that treat inflammation. Giving Canakinumab, a drug to block inflammation, to people with high, normal or low blood cholesterol levels has been shown to help prevent heart attacks even though it does not lower cholesterol (N Engl J Med, Sept 21, 2017;377:1119-1131). See Blocking Inflammation to Prevent Heart Attacks

While statins are routinely prescribed to lower cholesterol, reducing inflammation may be their most important function. The Jupiter study reported that giving statin drugs to people who had normal blood cholesterol levels and high levels of inflammation (C-reactive protein) resulted in 54 percent fewer heart attacks, 48 percent fewer strokes, 46 percent fewer angioplasties or bypass operations and 20 percent fewer deaths from any cause, compared with those taking placebos (NEJM, November 9, 2008).

My Recommendations

Inflammation can cause or contribute to heart attacks, strokes, some types of cancers, diabetes, obesity, auto-immune diseases, loss of muscle and bone, and many other diseases and conditions (J of the Am Heart Assoc, May 31, 2019). To a large degree, lifestyle changes can decrease inflammation, whether or not your doctor prescribes drugs

MAY 18

Running and Walking May Be Good for Your Back

People who run or walk regularly have healthier and stronger spinal discs than non-exercisers do (Scientific Reports 7, April 19, 2017). This is very reassuring because some doctors tell patients with back pain not to run because they think that the jarring of the foot striking the ground will damage discs and injure backs, even though there is no good data anywhere to support such opinions. However, if your back hurts when you run, you should stop running.

back.jpg

The vertebral bones of the spine are separated by pads called discs that absorb the shock of hard exercise such as running or lifting weights. The nerves that supply your body pass out from the spine between the vertebral bones where the discs are located. With aging or inactivity, the discs weaken and can be squashed between the much tougher vertebral bones. A squashed disc can protrude between the vertebral bones and may pinch nerves to cause excruciating pain.

Scientists have known for hundreds of years that lack of exercise weakens muscles and bones, while exercise strengthens them (Sports Med, 2016;46:1165–1182), but until recently, no good studies have shown that exercise also strengthens discs. Some doctors believe that rapid movements and pressure will damage discs, but several animal studies show that a regular exercise program strengthens discs (Eur. Spine J, 2011;20:1796–1812), makes discs larger and stronger (Spine, 2012;37:1440–1447) and strengthens discs in rat spines (Spine, 2010;35:1429–1436). Now we have data that a regular exercise program strengthens human discs and is probably the most effective means of treating many cases of back pain caused by weak or damaged discs (Sports Med, 2016;46:473–485). We also have strong MRI data that people who run or walk regularly have larger and stronger discs that contain more fluid to pad and protect them from injury (Scientific Reports 7, April 19, 2017).

Back Surgery Has an Incredibly High Failure Rate

A spinal fusion includes surgery to remove at least part of a disc and a bone graft to fuse the upper vertebral bone to the lower vertebral bone. Many reports show that regular back exercises are usually more effective than this surgery to treat back pain caused by disc compression (Ann Rheum Dis, 2010;69:1643–1648). In spite of this, the number of spinal fusions performed in the U.S increased progressively until 2012. Then the rates of spinal fusions decreased, primarily because Blue Cross of North Carolina and several other insurers refused to pay for the procedure (The Spine Journal, February 1, 2015;15(2):265–271). This implies that the rate that some surgical procedures are done is driven by insurers’ willingness to pay for a procedure.

My Recommendations

• If you have back pain, you should check with your doctor for a specific diagnosis and treatment.

• Specific daily back exercises are the primary treatment for most causes of chronic back pain. Realize that some conditions can be worsened by exercise.

• If you have a condition that is treated with exercise, you should get instructions from a physical therapist who can teach you specific belly and back exercises and how to use exercise machines properly. Improper exercise can worsen your condition.

• Start off with very low resistance and stop immediately for the day if the pain worsens. The best indicator of damage from exercise is pain. Listen to your body.

• Try to exercise every day and do not do anything that increases pain in the injured area.

APRIL 30

Recreational Exercise Better Than Physically Active Jobs

A new study from Denmark shows that while leisure-time physical activity is associated with reduced heart attack risk, occupational physical activity is associated with increased risk (European Heart Journal, April 14, 2021;42(15):1512–1515). The Copenhagen General Population Study followed 104,046 participants for 10 years and found that compared to low levels of leisure-time physical activity, moderate, high and very high volumes of leisure-time physical activity reduced risk for heart attacks and death significantly, but the opposite was true for physical activity on the job. Participants with leisure-time physical activity had a 15 percent reduced risk for heart attacks, while those with heavy physical activity at work had a 35 percent increased risk.

Differences Between Leisure-Time and Work-Time Physical Activity
People who have physically demanding jobs often believe that they do not need to exercise because their work keeps them moving much of the time. However, there are differences between work and leisure activity:
• Recreational exercise is usually more intense and sustained for aerobic endurance, whereas work activity is usually repetitive motions of short duration at low intensity, such as standing for hours, walking up and down steps, moving arms to load boxes and so forth.
• Leisure time exercise improves cardiorespiratory and metabolic fitness and health, while physical activity on the job is associated with fatigue, insufficient recovery, elevated blood pressure and elevated heart rates.
• Heavy manual job workers are more likely to be stressed by noise, air pollution and other poor working conditions, and they may be too tired from their jobs to exercise after work.

Stable Plaques: A Possible Explanation
The authors of the Copenhagen study did not pursue reasons why there would be higher rates of heart attacks among people with high physical activity at work, but here is my opinion. Heart attacks are not caused by plaque buildup on the inner lining of arteries; they are caused by a sudden complete obstruction of the blood flowing to part of the heart muscle. The sudden complete obstruction of blood flow to a part of the heart muscle is usually caused by a plaque breaking off, followed by bleeding where the plaque broke off. Then clots form at the bleeding site, and the clot extends to block completely the flow of blood to the part of the heart muscle supplied by that artery. The part of the heart muscle deprived completely of blood flow then dies, to cause a heart attack.

Older endurance athletes may have more plaques in their arteries than non-exercisers, but they often have the type of plaques that are far less likely to break off to cause heart attacks (Circulation, April 27, 2017;136:138-148; May 2, 2017;136:126-137). They have:
• low 10-year-history risk scores for suffering heart attacks (Framingham study data),
• greater plaque thickness,
• more calcium in their plaques,
• wider and more dilated arteries that are far less likely to be blocked, and
• more stable plaques that are far less likely to break off to cause heart attacks.
A study of 21,758 men, average age 51.7 years, followed for an average 10.4 years, showed that men who exercised the most can have more plaques in their arteries, but did not suffer more heart attacks or deaths than those with less heart artery calcification (JAMA Cardiol, Jan 30, 2019). The least active men with excessive arterial plaques were twice as likely to die of heart disease. Compared to low-level exercisers, the heavy exercisers without increased plaques had half the risk of dying during the study period. See Stable Plaques: Why Exercisers Have Fewer Heart Attacks

How to Measure Plaque Stability
Your doctor can help to predict your risk for a heart attack with a test called a Calcium Score, which is a special CT X ray or sound wave test that measures the thickness of plaques on the inner lining of arteries. A CT scan can also show how stable a plaque is. It can show the difference between stable plaques that are usually safe and those that are unstable and more likely to break off to cause heart attacks (American Journal of Roentgenology, March, 2015;204(3):W249-W260). Signs of plaque stability include extensive calcification, less lipid-rich areas, increased fibrous areas and structural changes.

My Recommendations
We do not know why leisure-time exercise appears to give you stronger protection against suffering a heart attack than having a job that requires you to be physically active. It is my opinion that the recreational activity is usually more intense and sustained than repetitive-motion movements at work and therefore may be more likely to stabilize plaques so they do not break off to cause a heart attack. The Copenhagen study suggests that even if you have a job that involves a lot of physical effort, you should still have a program of recreational exercise that gives you the benefits of aerobic activity.

APRIL 27

Do you have an injury or you know somebody that has an injury a chair work out they can perform keep up their fitness and blood circulating in their body

April 27

Research on Intense Exercise

The more intensely you exercise, the less likely you are to suffer a heart attack, even though heart attacks can be caused by intense exercise in some people who already have irregular heartbeats or blocked arteries leading to their hearts.

• Researchers had 4582 men and women, average age 46, wear mechanical accelerometers to measure their intensity of exercise. After ten years, they found that the more they moved about and the less time they sat without moving around, the less likely they were to develop heart disease and the higher their blood levels of the good HDL cholesterol (Preventive Medicine, published online May 02, 2019). Also, the women who were even moderately active had lower total cholesterols.

• The HUNT study from Norway followed 26,163 healthy men and women, average age 55.7, for an average of 13 years and found that the more fit they were, the less likely they were to develop a first heart attack (Journal of the American Heart Association, April 19, 2019). They found that a high level of fitness was even more protective in the women than in the men.

• The SUN study from Spain followed 18,737 men and women, average age 38, for six years. The researchers found lower rates of heart attacks in those who exercised intensely as opposed to those who exercised at low intensity (American J of Cardiology, Dec 1, 2018;122(11):1871–1878). They used intensity of exercise per time spent exercising to show that those who exercise intensely had half the heart attack rate, compared to those who did the same amount of exercise less intensely.

Exercise to Prevent a Heart Attack

The association between a regular exercise program and improved health is unquestioned (J Clin Prev Cardiol, 2017;6:109-14; Am J Lifestyle Med, July 1, 2009;3(1 Suppl):44S–49S), and a healthful diet in addition to exercise helps even more to help prevent heart attacks and many other diseases (Eur J Prev Cardiol, Jul 2018 ;25(11):1186-1197).

Intensity makes all muscles stronger including your heart muscle. All people lose heart muscle as they age, which increases risk for frailty and heart failure. Strengthening your heart muscle helps you to live a more vigorous lifestyle and to protect you from heart failure. Intense exercise stabilizes plaques in arteries and widens heart arteries to help protect you from a heart attack. Men with the highest ability to take in and use oxygen (VO2max) have the least high blood pressure, high HBA1C (a test for diabetes), high fasting blood sugar levels, obesity, coronary calcium scoring, abnormal treadmill exercise test, and calculated 10-year risk for heart attacks (American J of Cardiology, March 2012;109(6):839-843).

Preventing heart attacks involves both exercising and eating healthfully. Since exercise helps to stabilize plaques to help keep them from breaking off from arteries, exercise should be part of any heart-attack-prevention program. Dedicated exercisers who need to eat large amounts of food to meet their caloric needs should choose healthful, anti-inflammatory foods to avoid forming more plaques in their arteries. Check with your doctor if you have evidence of heart disease caused by a faulty diet: high blood pressure, high blood cholesterol, high triglycerides, high blood sugar, high CRP (c-reactive protein, a measure of inflammation), an abnormal EKG, or chest pain, particularly with exercise.

Can Intense Exercise Be Harmful?

Exercisers live longer and have far less heart damage than non-exercisers. However, elite athletes may be at increased risk for irregular heartbeats, increased arterial plaque size or thickened heart valves.

• Even though master athletes may be at increased risk for irregular heartbeats (atrial fibrillation), they can still benefit from continuing to exercise. Compared to non-exercisers with atrial fibrillation, they appear to be at reduced risk for suffering from serious side effects such as clots. See Irregular Heartbeats in Senior Athletes and Exercisers.

• Elite athletes may be at increased risk for larger plaques in their arteries than non-exercisers, but narrowing of arteries by plaques does not cause a heart attack. Heart attacks are caused by plaques breaking off from arteries, and exercise helps to prevent heart attacks by making plaques more stable and less likely to break off. See Exercisers Have More Stable Plaques.

• Vigorous exercisers may be at increased risk for thickened heart valves, but compared to non-exercisers, athletes with thickened heart valves still have stronger heart muscles so that they are less likely to suffer heart failure. See Exercise to Prevent a Heart Attack

My Recommendations

I think everyone should have a regular exercise program, and it is never too late to start. See How to Start an Exercise Program.

• Before you try to increase the intensity of your exercise program, you should have exercised regularly for many months, be in good shape and not have any health conditions that can harm you. Because intense exercise can cause heart attacks in susceptible people, you may want to check with your doctor before increasing the intensity of your workouts.

• Try to set up your exercise program so that you increase the pace enough on an intense day to feel mild muscle soreness on the next day. Then take easy workouts for as many days as it takes for the soreness to go away. Only then should you take your next hard workout.

• When you are training properly, your muscles can feel sore every morning. If they don’t feel better after a 10 minute warm-up, take the day off.

• If you feel pain in one spot that does not go away after you slow down, stop that workout immediately for that day. Otherwise you are likely to be headed for an injury.

CAUTION: Intense exercise can cause a heart attack in a person who has blocked arteries or heart damage. Check with your doctor before you start a new exercise program or increase the intensity of your existing program.

APRIL 23

Exercise Every Day or Every Other Day?

The old guideline recommending 30 minutes of exercise three times a week just isn’t enough, according to the latest research. Athletes know that they need to work out every day, and all people who just want to stay healthy can benefit from the same type of exercise program.

Why Athletes Need to Exercise Every Day

Knowledgeable athletes train by stressing and recovering. You have to damage muscles to gain strength and enlarge muscles. You become more fit by taking a hard workout and then resting for a day or two than you will by exercising at the same leisurely pace every day. Every muscles is made up of thousands of fibers like a rope is made of many strands. Every fiber is made up of blocks called sarcomeres that fit end to end like a row of bricks. Sarcomeres butt upon each other, end-to-end, at Z-lines.

Muscles contract only at each Z-line. When you exercise vigorously, you damage these Z-lines and when they heal, the muscle fibers are stronger. So all athletes train by stressing and recovering. On one day, they take an intense workout to damage their muscles at the Z-lines. On the next day their muscles are sore and damaged and they exercise at a relaxed pace. When the muscles are healed and the soreness lessens, they take their next intense workout.

If athletes exercise at low intensity during the healing phase of the Z-lines, their muscle  fibers will become stronger than if they rest. If they exercise vigorously when their muscles are sore, they are likely to tear them and be injured. Athletes need to exercise every day to gain maximum strength.

Why Non-Athletes Also Should Exercise Every Day

Forty percent of North Americans die of heart attacks. One of the common causes of the arterial damage that precedes heart attacks is a high rise in blood sugar after meals. Blood sugar always rises after meals and because of faulty lifestyle habits, most North Americans have blood sugars that rise too high. Resting muscles remove no sugar from the bloodstream, but contracting muscles remove sugar rapidly from the bloodstream and can do so without even needing insulin. This effect is strongest during exercise and diminishes to no benefit after about 17 hours. If you want to use exercise to help control blood sugar, you need to do it every day.

An Exercise Program for Everyone

Because a person with blocked arteries leading to the heart could suffer a heart attack during exercise, please check with your doctor before starting a new exercise program. Whatever activity you choose, try to exercise every day. If you are just starting out, spend about six weeks at a slow pace until you are comfortable in your activity. Then you are ready to alternate more intense days with easier workouts.

Intense Days

Stress refers to intensity, not the length of your workout. You can gauge the severity of the stress by the amount of burning you feel in your muscles during exercise. interval training means that you start out slowly, pick up the pace, slow down immediately when your muscles start to burn, recover by going very slowly for as long as you want, and then pick up the pace again.

On your hard days, warm up by going very slowly for five to 10 minutes. Going slowly at the start of a workout warms up muscles to help make them resistant to injury. If your muscles still feel tired or heavy, do not try interval training. Exercising with tired or sore muscles can cause serious injuries.

After you warm up, pick up the pace gradually until you feel burning in your muscles and immediately slow down. Then go at a very slow pace until the soreness goes away, your breath returns to normal and you feel recovered. How long it takes to recover is irrelevant. You take your next faster pick up when you feel that you have recovered, not from any preset time. Then pick up the pace until you feel burning again.

If you don’t compete, you do not ever need to go at 100 percent intensity. People who are just starting to do interval workouts should pick up the pace only slightly and not become short of breath. Slow down and get out of the burn as soon as you feel it. As soon as the burning and fatigue go away, and you are not breathing hard, try to pick up the pace again. In early workouts, you may only be able to do one hard pickup after you have just started your workout. Do not start your next pick up until your legs feel fresh. As soon as your legs start to feel heavy, stop the workout. Trying to increase the pace when your muscles feel sore and heavy invites injury.

Easy Days

The day after your hard workout your muscles will probably feel sore and you should take an easy workout. If the discomfort does not go away as you continue to exercise, is worse on one side of your body, or increases as you exercise, stop exercising immediately. You are injured and continuing to exercise will delay healing. Take off the next day also if you still feel sore in one place. If you feel better as you exercise casually, continue to exercise until you feel any discomfort or heaviness. Always stop every workout when your muscles feel heavy or sore. Keep on taking easy days where you exercise at low intensity until you feel fresh again. Do not do another hard workout until the soreness in your muscles has gone away.

My Recommendations

Every healthy person should try to exercise every day. You will gain a much higher level of fitness by “stressing and recovering”. That means to exercise more intensely on one day, feel sore on the next and go slowly. Only when your muscles feel fresh should you try to pick up the pace again.

April 19

Don’t Use Aspirin or NSAIDs for Muscle Pain from Exercise

  May 5, 2019  6255  

Some athletes and exercisers take pain medication (aspirin or NSAIDs) because they think it may prevent muscle soreness or will help them to heal faster after a workout. However, taking pain medicines before or during exercise will not block pain, help you to exercise longer or recover faster from exercise. They can increase risk for bleeding and damage to muscles, tendons or kidneys, and they can also delay muscle recovery from exercise. I believe that you should not take aspirin or NSAIDs (nonsteroidal anti-inflammatory drugs) before, during, or soon after exercising unless your doctor specifically recommends that you need to take them.

• Aspirin increases risk of bleeding into your stomach, brain, or any area that is bumped in an accident. Aspirin kills as many people by causing major bleeds as it saves by preventing heart attacks (JAMA, Jan 22, 2019;321(3):277-287). Caution about stopping daily aspirin: Do not stop taking aspirin suddenly. If you want to stop taking aspirin after taking it for a while, your doctor will tell you how to gradually taper your dose.
• NSAIDs do not block the muscle burning you feel when you exercise intensely (Med Sci in Sports and Exercise, Aug 1997;29(8):0999-1012). When you exercise intensely, you run low on oxygen which causes lactic acid to accumulate in muscles to cause muscle burning. The only way that you can stop this muscle burning during intense exercise is to slow down to allow lactic acid to be cleared.
• NSAIDs taken the next day may reduce delayed-onset muscle soreness (DOMS), but do not increase the rate of recovery from exercise (J Strength Cond Res, Feb 2003;17(1):53-9).
• NSAIDs reduce new muscle protein synthesis after intense exercise (Am J Physiol Endocrinol Metab, Mar 2002;282(3):E551-6), and reduce muscle growth after intense exercise (Sports Med, Dec 1, 2012;42(12):1017-28).
• Aspirin decreases protein synthesis after exercise (J Biol Chem, April 2007;282(14):10164-71).
• Taking NSAIDs after injuries delays healing (South African Medical Journal, Jun 6, 1995;85:517-522), and taking NSAIDs for several weeks after a fracture delays the healing of broken bones (J Orthop Trauma, May 1995;9:392-400).

Common types and brands of NSAIDs include ibuprofen (Motrin, Advil), indomethacin (Indocin), ketoprofen (Ketoprofen) and naproxen (Aleve, Anaprox, Naprelan, Naprosyn).
Also see NSAIDs Interfere with Exercise Training
NSAIDs May Block Gains in Endurance and Strength

APRIL15

Exercise and the Gut Microbiome

The hottest area of research in medicine today is about the bacteria in your colon called the microbiome. More and more studies show that exercise, in addition to a healthful diet, helps to increase the numbers of healthful bacteria in your colon that may prevent or treat obesity, diabetes, heart attacks, inflammation and even certain cancers (Ex and Sport Sci Rev, April 2019;47(2):75-85).

More than 100 trillion microorganisms live in your body (FEMS Microbiol Rev, 2014;38:996-1047) and weigh two to five pounds (PLoS Biol, Aug 19, 2016;14(8):e1002533). Of the more than 1000 different types of bacteria that live in your colon, some are healthful while others can be harmful (Nature, Jan 23, 2014;505(7484):559–563). The healthful bacteria are content to eat what you eat as food passes through your intestines, so they stay in your colon and do not try to cross into your cells and bloodstream. Healthful colon bacteria can form metabolites that help to prevent obesity, diabetes, heart attacks and even depression. On the other hand, the harmful bacteria are not happy with your food supply so they try to find food somewhere else by invading the cells lining your colon. Your immune system responds by producing proteins and cells that attack and try to kill the invading bacteria. If the invading bacteria continue to try to penetrate your cells day after day, your immune system stays active all the time. This is called inflammation. The same antibodies and cells that are supposed to kill invading germs can attack and damage your arteries to cause plaques to form, and can damage your DNA to cause cancer (PLoS One, Apr 13, 2017:12(4):e0176062). The harmful bacteria can also convert nutrients in your colon to other chemicals that can be harmfuland cause diseases.

Exercise Can Increase Good Bacteria in Your Colon
In 2016, researchers showed that exercise increases the number of healthful gut bacteria in mice and decreases the numbers of harmful ones (PLoS One, Mar 8, 2016;11(3):e0150502.) A later study showed that just six weeks of exercise markedly increased levels of healthful gut bacteria in humans, and after the study subjects stopped exercising, the levels of healthful gut bacteria dropped to their previous lower levels (Med Sci Sports Exerc, Apr 2018;50(4):747-757).

There are many theories on how healthful gut bacteria dampen inflammation to help prevent disease (Gut Microbes, Mar 4, 2018;9(2):115-130). Healthful intestinal bacteria:
• convert soluble fiber in your colon into short chain fatty acids (SCFAs) that dampen inflammation, lower high cholesterol and blood pressure, and help you lose excess weight (Diet Microbiome Health, 2018:299–345).
• markedly reduce pro-inflammatory cell-signaling proteins and increase anti-inflammatory ones, as well as antioxidant enzymes (Exercise and Sport Sciences Reviews, April 2019;47(2):75-85)
• lower high blood sugar to help prevent diabetes (Annual Rev Med, (2011) 62:361–80)
• increase mucus production to help protect the colon linings from harmful bacteria
• increase intestinal motility (J Neurogastroenterol Motil, 2012; 18(1):64–9) and push gas through (Am J Med, 2004; 116(8):536–9) to move food faster through the intestines and help to prevent constipation
• increase the circulation of bile acids from the liver; accumulation of bile acids increases inflammation (J Hepatol, 2013; 58(5):949–55).

My Recommendations
You can help to prevent heart attacks and certain cancers by adopting a lifestyle that promotes the growth of healthful bacteria in your colon and reduces inflammation:
• Try to exercise every day
• Eat a plant-based diet with lots of vegetables, fruits, whole grains, beans, nuts and other seeds
• Restrict pro-inflammatory foods, such mammal meat, processed meats, fried foods, and drinks with sugar in them
• Avoid being overweight
• Avoid smoke and alcohol

APRIL 5

More Reasons to Exercise as You Grow Older

Muscles are made up of thousands of muscle fibers just as a rope is made up of many strands. Each muscle fiber has a nerve that innervates it. 

With aging you can lose nerve fibers that, in turn, cause you to lose the corresponding muscle fibers, but exercising against resistance will make the remaining muscle 

fibers larger so they can generate more force.

A recent experiment measured the force that a rat’s muscle fiber generates when it is electrically stimulated at the nerve or at the muscle. 

Electrically stimulating the muscle directly showed that the muscles of young rats generated 40 percent more force than those of old rats. On the other hand, when t

he nerve endings were stimulated electrically for five minutes, the muscles of the old and young rats generated the same amount of force. 

The authors suggest that loss of strength with aging is primarily due to loss of nerve function rather than just muscle function (Experimental Gerontology

March 2018). The repetition of a regular and consistent training program teaches your brain how to contract your muscles more efficiently.

Researchers at the University of Guelph have another explanation why people, even those who exercise regularly, 

lose muscle size and strength as they age. They showed that aging causes loss of mitochondria, the tiny furnaces in 

cells that turn food into energy (Cell Reports, March 13, 2018). This causes the accumulation of breakdown 

products called Reactive Oxygen Species (ROS) that delay healing and weaken muscles (Cell Metabolism

March 2017;25(3):581–592).

More New Studies on Muscle Growth for Older People

• Osteoporosis: Lifting weights helps to strengthen bones of postmenopausal women who suffered from os

from increasing their intake of protein above the current RDA (recommended dietary allowance) of 0.8 gm/kg of body weight/day. Even older men who are taking extra testosterone 

do not gain any extra strength or muscle growth from increasing their intake of protein to 1.3 g/kg/day (JAMA Internal Medicine, April 2018).

• High-Plant Diet after Menopause: Older women who follow a Mediterranean-type diet (based on 

plants, with fish but restricting red meat and added sugars) have larger muscles and bones after the 

menopause than women who eat the typical Western diet (ENDO 2018, the Endocrine Society 

annual meeting in Chicago, March 19, 2018).

• Recovery Time: Older people who do strength training need to realize that their muscles 

will not heal as fast from workouts as muscles of younger people because aging causes their mitochondria

 to become smaller in number and size (Cell Metabolism, March 2017;25(3):581–592).

Starting a Resistance Program

The most effective way to slow down the loss of muscle strength with aging is to start a resistance 

exercise program that includes using strength training machines or lifting weights. A review of 25 well-designed 

and performed scientific studies shows that resistance training can grow larger and stronger

 muscles in older men and women (Sports Med, Dec 2015;45(12):1693-720). Older people who 

use strength training machines two or three times a week can make themselves stronger to decrease their risk for 

falling, breaking bones, and suffering osteoporosis, arthritis, heart attacks, diabetes, and premature death (Am J Prev Med

Oct 2003;25(3 Suppl 2):141-9). See Slowing Loss of Bone and Muscle Strength with Aging

Before you start a new weight training program, check with your doctor and get expert advice 

from a trainer so you can learn proper lifting techniques for the equipment you will be using. 

Most beginners will be far more successful on weight lifting machines, rather than using free weights. 

The machines are safer because they can guide the way you move the weights with the specific muscles for each machine.

How to Make Muscles Stronger

Just exercising does not make a muscle stronger. The stimulus to make a muscle larger 

and stronger is to exercise that muscle against resistance to the point where you 

feel a burning in that muscle. However, if you continue to exercise after you start 

to feel that burn, you run the risk of injuring the muscle, so most older people 

can prevent injuries by stopping each set of lifting as soon they feel a burn in their muscles. 

You can exercise to the burn by using heavy weights with few repetitions or by using lighter 

weights with more repetitions. Older people gain the most strength by doing more sets 

of lower repetitions per set than using fewer sets with higher numbers of repetitions 

Per set (Experimental Gerontology, March 29, 2018;108:18-27). The lighter the weight you use, 

the more repetitions you have to do to feel the burn. For example, several sets of three repetitions

 each is safer than performing fewer sets of the same weight with sets of 10 repetitions. For more detailed suggestions see Strength Training Guidelines from Dr. Richard Winnett of Virginia Tech.

My Recommendations

Aging can take away much of your quality of life unless you keep your muscles strong 

enough to perform all of your daily activities. A regular strength training program will 

help you to move faster, walk with more security, be less likely to fall and hurt yourself, 

and have more confidence in every movement of your body.

CAUTION: People with blocked arteries leading to their hearts can suffer heart attacks 

with exercise. Check with your doctor before starting a new exercise program or increasing the intensity of your current program.

APRIL 2

Too Much Intense Exercise May Harm You

Exercising regularly helps to prevent disease and prolong lives, and exercising intensely can prevent disease and prolong lives even more (PLoS Medicine, January 12, 2021). However, a study from Karolinska Institute suggests that exercising intensely too often can harm your health, and perhaps even shorten your life (Cell Metab, Mar 13, 2021;S1550-4131(21):00102-9). This study showed that people who tried to do intense workouts on an almost daily basis developed severe damage to their mitochondria that markedly:
• reduced their ability to exercise by reducing their maximum ability to take and use oxygen, and
• increased their risk for suffering high blood sugar levels and diabetes by making their cells less responsive to insulin.

Mitochondria are chemical structures inside your cells that help to turn food into the energy needed to drive biochemical reactions. When participants in this study reduced the frequency of their intense workouts, their mitochondria recovered and their health and training problems disappeared.

Stress and Recover — The Basic Rule for Exercisers
Every healthy person should exercise by stressing and recovering because you gain more health benefits and a higher level of fitness by exercising more intensely on one day, feeling a little sore on the next day and then going at a slow pace for as many days as it takes for your muscles to feel fresh again.

Stress Days: On your stress day, warm up by starting out at a very slow pace, and then alternate a series of going a little harder and faster until you feel a slight burning or tightness in your muscles. Immediately slow down and go at a slow pace until you feel fresh again. In the beginning, you may want to pick up the pace for only 5 to 10 seconds (“intervals”). As you improve, you can work up to 30-second “intervals” at your harder pace. For non-competitive exercisers, you don’t ever need to stay in an intense “interval” for more than 30 seconds. You then go at a slow pace for as long as it takes for you to breathe normally and for your muscles to feel fresh again. When your muscles feel fresh, you can pick up the pace and slow down immediately when you feel a burning or tightness in your muscles again. Novice cyclists can do 5 to 10 pedal strokes, and then go slow for as long as they need to recover. Novice runners can start out by taking only 5 to 10 running steps. Swimmers can do short bursts of their favorite stroke, and so forth for any activity you choose. Continue to alternate these slight pickups of intensity until your muscles stop feeling better as soon as you slow down. Eventually you may want to work up to 30-second intervals. At your peak, your stress workout can include a 10 minute warmup, a maximum of 30 minutes of intervals, and a 5 to 10 minute cool-down.

Recovery Days: Your recovery days (“easy days”) will always be governed by how you feel. On the day after a stress day, your muscles will probably feel slightly sore and you are supposed to recover by going at a very slow pace. The muscle discomfort is called Delayed Onset Muscle Soreness (DOMS). You warm up by going very slowly, and if your muscles don’t feel more comfortable after a 5-10 minute warm up, take the day off altogether.
• If your muscles feel better after your warmup, go at an easy pace for as long as you like and stop your workout when your muscles feel any protracted discomfort. You are never supposed to work through pain. Always stop if you feel fatigue or muscle tightness or discomfort.
• Continue to take slow recovery days for as many days as it takes for your muscles to feel fresh after you warm up for 5-10 minutes. Only then should you take your next hard stress day workout. Most exercisers follow each stress day with one to three or more recovery days before they take their next intense workout.

How Often Should You Do A Stress Day?
Non-competitive exercisers can gain significant health benefits, such as lowered high blood pressure and body fat, with just one intense workout a week followed by six days for slow recovery workouts. You can harm yourself by doing stress workouts too often. In one study, exercisers who worked out intensely three times a week for six weeks did not lower their high blood pressures or body fat as much as those who exercised more casually five times a week. (Med Sci Sports Exerc, Dec 11, 2021).

You will recover faster from a hard workout by doing nothing at all, but going slowly on your recovery days causes more fibrous tissue to form in your muscles so that they are more resistant to injury.

How Can You Tell If You Are Exercising Too Much?
Most competitive athletes learn sooner or later that when they exercise intensely too often, they may suffer an overtraining syndrome in which they can’t train or race at all. There are no laboratory tests that will tell you that you are overtraining. You should take days off, or markedly reduce your workouts, if you suffer:
• any injury
• muscle soreness that does not go away after you warm up
• continued difficulty falling asleep or staying asleep
• continued loss of appetite
• continued fatigue or loss of energy
• recurrent or prolonged infections
• any illness (check with your doctor)
• a persistent increase in resting heart rate of more than 10 beats per minute
• decreased muscle strength, endurance, or ability to perform and recover from your regular workouts

If you are a competitive athlete who is suffering from overtraining, you need to go back to background work. These principles apply to any sport. For a runner, jog on the days that you can, and take days off when you feel sore. After several weeks, you will be able to start regular jogging and your muscles will feel fresh again. When this happens, you are ready to start training, but first you must promise yourself that you will never try to run fast when you feel soreness in your muscles and tendons. Set up a schedule in which you take a hard-fast workout, feel sore on the next day, and then go at an easy pace in your workouts until the soreness has completely disappeared. You may try to take a hard workout every third to seventh day, but skip a hard workout on any day that you still feel sore after you warm up.

My Recommendations
Exercise helps to strengthen your heart, prevent disease and prolong lives, and intense exercise one or more times a week increases these benefits. However, you should know the signs and symptoms of exercising too much and the warning signs of damage from excessive exercise. Non-competitive exercisers can do very well on one day a week of intense intervals followed by six days of easy exercise.

Caution: Check with your doctor before you start or increase the intensity of an exercise program, particularly if you have chest pain, heart attack risk factors or heart problems.

MARCH 30

How to Prevent Wear-and-Tear Injuries

You can help to prevent wear-and-tear injuries from any type of exercise by warming up, by stopping exercise when you feel pain and by not exercising intensely when your muscles feel heavy or sore. Muscles are made of millions of individual fibers. When you first contract a muscle, you use only one percent of the fibers. As you continue to exercise, you contract more fibers to share the load, which places less force on each fiber and helps to prevent injuries. Always warm up. Go slow before you go fast. If you take a hard workout and feel sore the next day, go easy on every day that your muscles continue to feel sore after you have warmed up. It usually takes at least 48 hours for muscles to recover from hard exercise. When you feel pain in one muscle during exercise, that’s a signal that it may be starting to tear and you should stop exercising for that day.

Runners Get More Injuries

If you think that football is the sport with the most injuries, you are wrong. Each year, 79.3 percent of long-distance runners suffer injuries that force them to take time off from running (Br J Sports Med, Aug, 2007;41(8):469-80). The most-injured part is the knee and the chance for an injury increases with running longer distances and having previous injuries. Injuries occur most often after a rapid increase in weekly distance, intensity, or frequency of hill or track workouts (Sports Med, 1996. Jan;21(1):49-72).

A survey of participants in a Rotterdam marathon found that:

• 55 percent of the runners had suffered serious injuries during the year before the marathon

• 15.6 percent of the runners reported at least one new lower extremity injury in the month before the race

• 18.2 percent reported injuring their legs during the marathon

• Immediately after the marathon, runners reported severe pain in two to four different parts of their legs

• One week later, most felt well enough to go back to work, even though almost all had painful muscles (Scand J Med Sci Sports, April, 2008;18(2):140-4).

Why Running Causes So Many Injuries

When you run, one foot is always off the ground, so each foot strikes the ground with a force equal to three times body weight (at 6-minute-mile pace) and the faster you run, the greater the force of each foot strike. Walking is much safer. When you walk, you always have one foot on the ground, so the force of a walking foot strike almost never exceeds your body weight. To convince yourself, place your hands on the huge quad muscles in the front of your upper leg while you run. Each time your leg strikes the ground, you will feel the muscle shake like jelly.

A study from the University of Wisconsin-La Crosse shows that as people start to feel tired during running, they shorten their strides and this decreases the force of their foot striking the ground (Medicine and Science in Sports and Exercise, Dec 1999;31(12):1828-33). The shorter stride lessens the force of their heel striking the ground and places it forward to the area behind the big toe. To compensate for the decreased force of their feet hitting the ground, they move their legs at a faster cadence. You can use this information to help you prevent injuries when you run. Shortening your stride will help to protect you from injuries by shifting your foot strike force forward. You can keep your speed by moving your legs at a faster cadence.

When You Need To Take a Day Off

The most common cause of injuries is not listening to your body when it talks to you. Every wear-and-tear injury you have had probably gave you signals long before you were injured. Most exercisers who are training properly have sore muscles every day when they wake up in the morning. However as they start to exercise, the soreness goes away and their muscles feel good. On days when your muscles do not feel better after you start to exercise, take the day off. If you are exercising and you feel discomfort in one or more non-symmetrical areas, stop exercising and take the day off. Pain in one area, such as a leg, and no discomfort in the other leg, is a strong warning of impending injury that could still be prevented.

Understanding How to Train Helps to Prevent Injuries

I think it is unwise to do the same workout at the same intensity every day because:

• it will not give you the same health benefits as a stress/recover training program,

• it will not make you a better athlete,

• it may increase your chances of injuring yourself,

• it will not help you to lose as much weight as you may want, and

• it makes no sense.

To strengthen your heart and increase your ability to take in and use oxygen, you have to exercise intensely enough to feel muscle burning and become somewhat short of breath. That stresses your muscles also. To make a muscle stronger, you need to exercise vigorously enough to damage it. You go a little faster on one day, damage the muscles and feel sore on the next day. This delayed-onset muscle soreness (DOMS) is evidence that you have damaged muscles. The soreness is a sign that you should spend that day exercising at a more relaxed pace and not put much pressure on your healing muscles.

In a stress/recover training program, you should set up your schedule to go a little faster with more intensity on one day, feel sore on the next day and go at low intensity for that day and as many additional days as it takes for the soreness to go away. Then, when the soreness is gone, you exercise more intensely again.

Arches and Running Injuries

Runners with high arches are at increased risk for suffering stress fractures, small cracks in the bones of their feet and lower legs. Those with low arches are at increased risk for knee cap pain. Your legs are shocked by the force of each foot hitting the ground, and the faster you run, the harder your foot strikes the ground. This force can break bones, damage joints and tear muscles. To protect yourself from this tremendous foot-strike force, your leg is designed so that you never are supposed to land flat-footed when you run. Almost all people land on the outside (lateral) bottom of the foot and roll inward toward the medial side where the big toe is. This is called pronation and helps to distribute the force of your foot strike throughout your foot and leg and protect you from injury. The further you roll inward, the greater the protection against this force. However, when you roll in too much, your lower leg twists inward excessively, causing your kneecap to rub against the long femur bone behind it and cause pain. Pain behind the kneecap is called Runner’s Knee which is one of the most common running injuries.

If you have pain behind the knee cap during running or walking, ask your podiatrist to look at your feet. If your arches appear to be flat, you usually will have a normal arch, but you roll inward so far that your arch touches the ground. Flat feet usually means that your foot rolls inward so far that the arch rolls all the way to touch the ground. If you have flat feet and no pain, you do not need to do anything. However if you have pain anywhere from your feet all the way up to your lower back, the treatment is to place special inserts called orthotics in your running shoes. You can also do special exercises that strengthen your vastus medialis muscle that pulls your knee cap inward.

If you develop pain in the medial side of your lower leg or your feet, your podiatrist will probably order a bone scan to check for stress fractures, small cracks in the bones of your feet. If you have stress fractures, you should stop running for a while and ride a bike, which causes no road shock. When you can run without feeling pain, you can start running again, but you should take shorter strides to decrease the force of your foot striking the ground. If you have high arches, you probably are not pronating enough to reduce the force of your foot strike. You can reduce the force of your foot strike by shortening your stride.

Strengthening Muscles Helps to Prevent Injuries

A study from Sweden showed that pre-season strength training for the hamstring muscles helped to prevent injuries to those muscles (Scandinavian Journal of Medicine & Science in Sports, 2003;13(4):244-250). Hamstring tears are very common soccer injuries, so players from two of the best soccer teams in Sweden were divided into two groups: a group that received specific hamstring training for 10 weeks, using a special device twice a week to overload the hamstrings eccentrically, and a control group that received no special training. The trained group had less than one third the hamstring injuries and also had greater improvement in hamstring strength and running speed. Muscles are injured when the force on them is greater than their inherent strength, so they tear. Resistance training makes muscles stronger so that they can withstand greater forces and therefore helps prevent injuries.

My Recommendations

• Do not do the same exercise at the same intensity every day. Use the hard/easy principle: faster on one day and much slower on the next.

• Always go much slower for several minutes before you go faster.

• If your muscles do not feel fresh after you have warmed up for a few minutes, take the day off.

• Stop exercising immediately if you feel pain in one area that worsens with exercise.

• Whatever your sport, understanding the principles of training helps to prevent injuries.

Caution: Almost everyone should exercise. Check with your doctor before you start a new exercise program or increase the intensity of your existing program. Blocked arteries leading to your heart can cause a heart attack during exercise.

MARCH 25

Muscle Cramps: Prevention and Treatment

Muscle cramps occur most often at night when you are sleeping, but they also can occur when you exercise vigorously, tear a muscle, or keep one leg in an awkward position, such as sitting in a chair in the same position for a long time. Muscle cramps are classified into those that occur during exercise and those that can occur at any time not related to exercise, usually at night.

Cramps That Occur During Exercise
Lack of electrolytes is a more common cause of muscle cramps during exercise than lack of water (BMJ Open Sport Exerc Med, Mar 5, 2019;5(1):e000478). Electrolytes are minerals that are essential for body functions, including sodium, potassium, calcium, bicarbonate, magnesium, chloride, and phosphate. Having low blood levels of sodium (salt) is a well-known cause of muscle cramps (Clin J Am Soc Nephrol. 2007;2:151–161). Dehydration, by itself, is a far less common cause of cramps (Br J Sports Med, 2013 Jul;47(11):710-4). You can be salt deficient and still have normal blood levels of electrolytes.

Researchers in Australia studied runners who drank either plain water or an electrolyte solution before and after exercise. They found that the runners were at increased risk for suffering muscle cramps when they drank plain water, probably because water dilutes the electrolyte concentration in the body and doesn’t replace what they lost through sweating (J Int Soc Sports Nutr, Mar 15, 2021;18(1):22). In this study, 10 men ran multiple sessions on a downhill treadmill in a hot (95 degree F) room for 40 to 60 minutes, to sweat enough to lose 1.5-2 percent of their body weight (about two pounds). They were then tested before, immediately after and 40 minutes after exercising, with two trials: first, drinking plain water; and second, drinking an electrolyte solution. The tests used a special device that electrically stimulated their calf muscles enough to cause muscle cramps. The runners developed muscle cramps on much lower electrical stimulation frequencies after drinking plain water than after drinking the electrolyte solution. These results suggest that lack of electrolytes is more likely to cause muscle cramps than just lack of water (dehydration).

Cramps are more likely to occur in hot weather because muscles fatigue earlier with higher temperatures. Cramps are more likely to occur during intense exercise that requires you to use your fast twitch strength fibers that fatigue earlier than your slow twitch endurance fibers.

Night-Time Leg Cramps
Up to 60 percent of North American adults suffer from occasional night-time leg cramps, a sudden painful contraction usually of the calf muscles that can last from a few seconds up to 10 or more minutes. Doctors do not know what causes these cramps, but most of the time, they are not caused by dehydration or lack of minerals. The leading theory is that most night-time leg cramps are caused by lack of a normal nerve reflex that causes a muscle fiber to relax when it is held in contraction (J Sports Sci, 1997 Jun;15(3):277-85). That is why people who suffer recurrent leg cramps should be checked for:
• all conditions that can cause nerve damage, including lack of vitamin B12 and diabetes
• all conditions that can cause blood vessel damage such as arteriosclerosis
• partially obstructed blood vessels
• pinched nerves in the back
• muscle damage
• abnormal mineral levels
• abnormal hormone levels such as low thyroid
• kidney disease
• arthritis
• dehydration
• use of several medications such as statins, birth control pills, diuretics, steroids, asthma medication such as albuterol, raloxifene, naproxen, or teriparatide (BMJ Clin Evid, 2015:1113).
If you have recurrent night-time leg cramps, check with your doctor.

What Causes Leg Cramps?
When you turn during sleep, you contract your calf muscles which stretches their tendons. This stimulates nerve stretch receptors in the tendon and sends a message back to the spinal cord, telling the calf muscles to contract. After you contract a muscle, reflex messages are sent along nerves to the spinal cord to relax that muscle. If the message to relax that muscle is blocked, the muscle stays contracted and you develop a cramp. Cramping during sleep is usually due to an exaggeration of the normal muscle reflex that causes the muscle to stay contracted and hurt. Older people and those who do not exercise are at increased risk for leg cramps because they have smaller and weaker muscles.

Preventing Night-Time Leg Cramps
If you do not have a serious cause, you can often prevent night cramps by:
• exhausting the stretch reflex before you go to bed by stretching your calf muscles (using wall pushups or a similar exercise)
• applying a heating pad for 10 minutes before you go to sleep
• starting a regular supervised exercise program to strengthen your calf muscles. If you are a non-exerciser, I recommend a stationary bicycle.

The only drug that has been shown to be effective in preventing night-time leg cramps is quinine (Brit Med J, Jan 7, 1995;310(6971):13-17), but the U.S. Food and Drug Administration stopped over-the-counter marketing of this remedy because of concerns about irregular heartbeats. Doctors can still prescribe quinine pills for relief of leg cramps, but since they can cause birth defects and miscarriages, they should never be taken by a pregnant woman. Quinine can also cause ringing in the ears, headache, nausea, disturbed vision, chest pain, asthma and other problems. Some people may benefit from calcium channel blockers, such as amlodipine, or Carisoprodol (a muscle relaxer that blocks pain).

Treating a Leg Cramp
When you get a leg cramp, stop whatever you are doing and try to gently walk it out while you massage the contracted muscle with your hands. Never put force on the contracted muscle because you may tear it. If the cramp continues, apply cool compresses, which can relax the contracted muscle and numb pain. Keep on gently massaging the muscle.

My Recommendations
Most leg cramps are harmless, but frequent muscle cramps can be a sign of serious medical conditions. If you suffer leg cramps only during exercise, eat salty foods or drink electrolyte solutions, not plain water, before and after you exercise. If that doesn’t stop the cramps, you need a complete medical work up. People who suffer frequent night-time leg cramps that do not respond to the simple steps listed above also need a detailed medical work up. Check with your doctor.

MARCH 16

Why World Records in Endurance Sports Events Keep Getting Faster

On May 6, 1954, Roger Bannister ran the first sub-four-minute mile. In the 66 years since that world record was set, more than 1600 men have run sub-four-minute miles (Track & Field News, May 2019). The current world record is 3:43.13.

The incredible improvement in world records in endurance events in all sports is mostly due to changes in training techniques, with workouts that are now so intense that they cause a lot of muscle fiber damage and the athletes have to spend more days doing slower recovery workouts. For example, 50 years ago, endurance runners would run fast interval workouts twice a week and also race or run long distances fast. That meant that they usually ran intervals on Tuesday and Thursday and a long run or race on weekends. They would allow only one day to recover from an interval workout. Today the interval workouts are so brutal that the athletes usually allow at least two days for slow recovery workouts after each intense day, so they are doing more intense workouts less often.

What are Intervals?

In intervals, you run a short distance very fast, slow down until you recover your breath, and then repeat alternating the very fast runs followed by much slower recovery runs until your muscles feel stiff and sore. For example, a top runner may run a quarter mile in 60 seconds, followed by a slow jog for an eighth of a mile and repeat it 12 or more times. That means that they are training at 4-minute-mile race pace.

Lack of Oxygen is the Limiting Factor

The limiting factor to how fast you can move over distance is the time it takes for oxygen to go from your red blood cells into your muscles. When you run fast, your muscles use large amounts of oxygen to burn carbohydrates, fat and protein for energy. You get most of the power to move your muscles from each of several successive chemical reactions, called the Krebs cycle. If you can get enough oxygen to meet your needs, food you have eaten is converted all the way to carbon dioxide and water that you blow off from your lungs when you breathe out. However, if you run so fast that your lungs cannot supply all the oxygen that you need, the series of chemical reactions slows down, you start to accumulate large amounts of lactic acid in your muscles, and the lactic acid spills over into your bloodstream. The lactic acid and carbon dioxide make your blood acidic and the acid burns your muscles to make them feel hot and painful. (Your non-exercising muscles do not burn because they are not accumulating large amounts of lactic acid inside their cells). You then try desperately to breathe hard enough to get rid of the acidity in your blood by taking in enough oxygen to get rid of the excess lactic acid and blow off the excess carbon dioxide that is accumulating in your blood.

Competitive Runners Must Run Up Severe Oxygen Debts in Training

Running fast enough to cause severe oxygen debts in training helps you to:

• tolerate higher blood levels of lactic acid,

• strengthen your heart and lungs so you can bring in more oxygen to your muscles, and

• help your muscles to convert lactic acid to be used as energy to fuel your muscles.

George Brooks at the University of California in Berkeley has shown that lactic acid is the chemical that requires less oxygen to power your muscles than any other source of fuel (Cell Metab, 2018 Apr 3;27(4):757-785). The marked accumulation of lactic acid in your muscles during training causes muscles to use more lactic acid as their primary source of energy in races. Lactic acid requires less oxygen than almost anything else to power your muscles, so by doing this, your muscles require less oxygen and you catch up on your oxygen debt. This neutralizes the acidity in your blood, so your muscles stop burning and hurting and you can pick up the pace.

Getting Your Second Wind

The muscle burning and shortness of breath caused by the accumulation of lactic acid forces you to slow down. We used to think that “second wind” meant that you slowed down to allow yourself time to recover from your oxygen debt, but research from the University of California in Berkeley gave another explanation (Fed Proc, 1986;45:2924-2929). After you slow down briefly, you feel better and could pick up the pace because the same lactic acid that caused the burning in your muscles and shortness of breath could be used as an efficient source of energy for your muscles. Since lactic acid requires less oxygen to power your muscles than most other sources of energy, you catch up on your oxygen debt, the concentration of lactic acid in your muscles drops, the burning and gasping lessens, you feel better and you can pick up the pace. Of course, when you keep on pushing the pace, you can again accumulate large amounts of lactic acid in muscles, which will make them burn and hurt again (Am J of Physiol-Endocrin and Metab, June 2006).

Using This Information to Have Greater Speed and Endurance

Since you can move faster in races by increasing the rate of forming and removing lactic acid, you should train intensely enough to accumulate large amounts of lactic acid in your body. Exercising with high blood levels of lactic acid stimulates your body to make more enzymes that turn lactic acid into a source of energy and strengthens your heart to be able to pump more oxygen to your exercising muscles. That is why virtually all athletes in sports that require speed over distance use some form of high intensity interval training.

You also need to eat carbohydrate-rich foods to be able to increase the meager amount of sugar that you can store in your muscles and liver. Carbohydrates are the source of the sugar, glucose, that is converted to the energy-efficient lactate during exercise. Lactate is used as a very oxygen-efficient fuel during exercise and also helps to replenish liver sugar stores during exercise.

MARCH 12

Weight Lifting for Middle-Aged and Older People

A resistance exercise program can help to slow the loss of muscle fibers and improve mobility as people age (Physiol Rev, Jan 1, 2019;99(1):427-511). Lifting weights or using Nautilus-type resistance training machines will strengthen your skeletal muscles, help to prevent broken bones from falls, and make your heart stronger to reduce risk of heart failure. Running, walking, riding a bicycle or playing tennis will not prevent the loss of muscle strength and size that occurs with aging. After age 40, most people lose more than eight percent of their muscle size per decade and by age 70, the rate of muscle loss nearly doubles to 15 percent per decade, markedly increasing risk for disability and disease (Am J Epidemiol, 1998;147(8):755-763).

Virtually all middle-aged and older people should do some form of resistance exercise, since extensive data show that having weak arm and leg muscles:

• increases risk for diabetes, heart attacks and premature death (British Medical Journal, Sept 2009; J of Phys, Sept 2009)

• is associated with smaller and weaker upper and lower chambers of your heart (J Am Geriatr Soc, Dec 2019;67:2568-2573)

• predicts death in people who have chronic heart failure (Cardiology, March 25, 2019). Heart failure means that the heart became too weak to pump adequate amounts of oxygen to the brain.

How to Build Muscle Without Injuries

When middle-aged and older people start a weight lifting program, they often get injured, usually because they try to train like young people who pick the heaviest weight they can lift ten times in a row and do three sets of ten lifts. They feel sore for the next few days and when the soreness goes away, they lift heavy weights again, usually two or three times a week. This type of training almost always injures older novice weight lifters and ends their training program. The best way for middle-aged and older people to prevent injuries is to lift lighter weights. You can gain almost the same muscle growth and strength by lifting a lighter weight many times as you do by lifting a heavier weight fewer times (J Appl Physiol, Jul 1, 2016;121(1):129-3).

Why You Lose Muscle Strength and Size with Aging

Muscles are made up of hundreds of thousands of individual fibers, just as a rope is made up of many strands. Each muscle fiber is innervated by a single motor nerve. With aging, you lose motor nerves, and with each loss of a nerve, you also lose the corresponding muscle fiber that it innervates. For example, the vastus medialis muscle in the front of your thigh contains about 800,000 muscle fibers when you are 20, but by age 60, it probably has only about 250,000 fibers. However, after a muscle fiber loses its primary nerve, other nerves covering other fibers can move over to stimulate that fiber in addition to stimulating their own primary muscle fibers. Lifelong competitive athletes over 50 who train four to five times per week did not lose as many of the nerves that innervate muscles and therefore retained more muscle size and strength with aging than their non-athlete peers (The Physician and Sportsmedicine, October 2011;39(3):172-8).

How Muscles Become Stronger

Each muscle fiber is made of a series of blocks called sarcomeres that are lined up end to end. Each sarcomere is attached to the one next to it at a “Z line.” Muscle fibers do not contract equally along their lengths; they contract only at each “Z line”. 

 To strengthen a muscle, you have to put enough force on the muscle to damage the Z-lines, as evidenced by bleeding and swelling into the Z-lines. You can tell you have damaged the Z-lines by the feeling of muscle soreness that begins 8 to 24 hours after you have lifted weights or done any form of resistance exercise. That is the time it takes for the swelling to occur in the Z-lines. This is called Delayed Onset Muscle Soreness (DOMS). Exercising your muscles intensely enough to damage them makes muscles stronger so they can withstand higher loads and be more resistant to injury.

When a muscle is damaged, your immune system sends to the damaged tissue large amounts of the same cells (lymphocytes) and chemicals (cytokines) that are used to kill germs when you have an infection. This causes inflammation, characterized by soreness (pain), increased blood flow to the injured fibers (redness), and increased flow of fluid into the damaged area (swelling). The immune cells release tissue growth factors to heal the damaged muscle fibers, and you should allow the muscle soreness to decrease or disappear before exercising intensely again. Muscle fibers become larger and increase in number by splitting to form new fibers. If you do not wait until the soreness goes away before exercising intensely again, the fibers can be torn, the muscles weaken and you can become injured.

A Rule for Gaining Muscle Size and Strength As You Age

Inexperienced weight lifters over 40 should not try to lift very heavy weights because that increases your chances of injuring yourself. Remember, it is recovery from damage to muscle fiber Z-lines that causes muscles to become stronger, so you can gain just about the same muscle growth and strength by lifting a lighter weight many times as you do by lifting a heavier weight fewer times (Dtsch Arztebl Int, May 2011;108(21):359-364). This type of resistance exercise can significantly increase muscle size and strength in older people

How to Start Your Resistance Training Program

If you are not already doing strength training, check with your doctor to make sure you do not have any condition that may be harmed by exercise. Then join a gym and ask for instructions on how to use the weight-training machines. On each machine, pick the weight that you can comfortably lift and lower 10 times in a row, without straining or hurting your muscles. Then move on to the next machine. End the workout immediately if you feel severe pain or if you have pain that does not go away as soon as you stop lifting the weight.

Take the next day off and return to the gym 48 hours later. If your muscles still feel sore 48 hours after your first workout, wait until the soreness is gone before you return to the gym. Try to use 15-20 of the strength training machines every other day or every third day. As you become stronger and the weights feel very easy for you, try to lift 15 times in a row, then perhaps 20 times. Only when you can lift that weight at least 20 times in a row, and not feel sore the next morning, should you try to increase the resistance by going to the next heavier weight on that machine.

The key to this program is to avoid injuring your muscles by lifting weights and increasing the number of repetitions gradually so that you do not cause muscle soreness that lasts longer than a day. You should not increase the weight (resistance) until you can lift a set of at least 20 repetitions on each machine without feeling sore the next morning.

My Recommendations

• Before you start any new exercise program, check with your doctor to rule out any conditions that might be aggravated by weight lifting.

• This program is designed for beginners and is intended to prevent injuries that plague older people when they first try to lift weights. It will not build very large muscles, but it will increase your strength and provide all of the other benefits of a weight training program. After many months (injury-free) on this program, if you wish to build larger muscles, you can transition to a more traditional weight training program; see Strength Training Guidelines. Otherwise, you can continue with this safe and effective program of resistance exercise for the rest of your life.

MARCH 5

Running and Walking May Be Good for Your Back

People who run or walk regularly have healthier and stronger spinal discs than non-exercisers do (Scientific Reports 7, April 19, 2017). This is very reassuring because some doctors tell patients with back pain not to run because they think that the jarring of the foot striking the ground will damage discs and injure backs, even though there is no good data anywhere to support such opinions. However, if your back hurts when you run, you should stop running.

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The vertebral bones of the spine are separated by pads called discs that absorb the shock of hard exercise such as running or lifting weights. The nerves that supply your body pass out from the spine between the vertebral bones where the discs are located. With aging or inactivity, the discs weaken and can be squashed between the much tougher vertebral bones. A squashed disc can protrude between the vertebral bones and may pinch nerves to cause excruciating pain.

Scientists have known for hundreds of years that lack of exercise weakens muscles and bones, while exercise strengthens them (Sports Med, 2016;46:1165–1182), but until recently, no good studies have shown that exercise also strengthens discs. Some doctors believe that rapid movements and pressure will damage discs, but several animal studies show that a regular exercise program strengthens discs (Eur. Spine J, 2011;20:1796–1812), makes discs larger and stronger (Spine, 2012;37:1440–1447) and strengthens discs in rat spines (Spine, 2010;35:1429–1436). Now we have data that a regular exercise program strengthens human discs and is probably the most effective means of treating many cases of back pain caused by weak or damaged discs (Sports Med, 2016;46:473–485). We also have strong MRI data that people who run or walk regularly have larger and stronger discs that contain more fluid to pad and protect them from injury (Scientific Reports 7, April 19, 2017).

Back Surgery Has an Incredibly High Failure Rate

A spinal fusion includes surgery to remove at least part of a disc and a bone graft to fuse the upper vertebral bone to the lower vertebral bone. Many reports show that regular back exercises are usually more effective than this surgery to treat back pain caused by disc compression (Ann Rheum Dis, 2010;69:1643–1648). In spite of this, the number of spinal fusions performed in the U.S increased progressively until 2012. Then the rates of spinal fusions decreased, primarily because Blue Cross of North Carolina and several other insurers refused to pay for the procedure (The Spine Journal, February 1, 2015;15(2):265–271). This implies that the rate that some surgical procedures are done is driven by insurers’ willingness to pay for a procedure.

My Recommendations

• If you have back pain, you should check with your doctor for a specific diagnosis and treatment.

• Specific daily back exercises are the primary treatment for most causes of chronic back pain. Realize that some conditions can be worsened by exercise.

• If you have a condition that is treated with exercise, you should get instructions from a physical therapist who can teach you specific belly and back exercises and how to use exercise machines properly. Improper exercise can worsen your condition.

• Start off with very low resistance and stop immediately for the day if the pain worsens. The best indicator of damage from exercise is pain. Listen to your body.

• Try to exercise every day and do not do anything that increases pain in the injured area.

MARCH 2

Statin Drugs and Exercise

The evidence is overwhelming that statin drugs do help to lower cholesterol and to reduce risk for heart attacks. However, one study confirms that statins interfere with the ability to exercise and to compete in sports, even in patients who report no symptoms (J Clin Endocrinol Metab, 2018;103(1):75-84). Statins cause muscle damage and reduced ability to exercise by decreasing the number and function of muscle mitochondria, the energy sources for muscles during exercise. This study agrees with others showing that statins interfere with a person’s ability to compete in sports (J Am Coll Cardiol, 2013;62(8):709–714). Up to 30 percent of patients who take statins suffer muscle pain or torn muscles (Eur Heart J, 2015;36(17):1012–1022), and people who exercise are far more likely to complain of muscle pain, muscle injuries and fatigue while taking statins (Br J Clin Pharmacol, 2004;57(4):525–528).

The Study

Twenty people who had taken statin drugs for many years were included in this new study. Ten suffered muscle pain and undue fatigue during exercise, while ten reported no symptoms during exercise or at rest. The authors used the following tests:

• maximal incremental cycling test,

• involuntary electrically stimulated isometric quadriceps muscle contractions, and

• biopsy of the vastus lateralis muscle.

Both groups had the same maximal endurance and maximal ability to take in air and use oxygen. However, compared to people who had never taken statin drugs, those who took statins (whether they reported symptoms or not) had:

• decreased anaerobic threshold (muscle pain and burning during exercise because of the accumulation of lactic acid in muscles from lack of oxygen),

• prolonged muscle relaxation time (delayed recovery from exercise),

• decreased rate of maximal force rise during exercise (loss of strength),

• reduced numbers of mitochondria in their muscles, and

• in the symptomatic statin takers only, reduced activity of mitochondria (decreased ability for muscles to use oxygen during exercise).

This shows that, compared to people who never took statins, the people who took long-term statins tired earlier during maximal exercise because they had lost some of their ability to take in and use oxygen, since their mitochondria could not use oxygen as efficiently to turn food into energy to power their muscles. This suggests that statins interfere with a person’s maximum ability to exercise long and hard, even in people who have no complaints.

My Recommendations

If your bad LDL cholesterol is above 100 or you have other factors that increase risk for a heart attack, most guidelines recommend that you take statin drugs to help protect you from suffering a heart attack. However, statin drugs come at a price. They can cause muscle pain and damage and can interfere with your ability to exercise. If you are a competitive athlete, they can interfere with your ability to compete at your best.

Studies show that strict lifestyle changes can be as effective as statins in lowering high blood levels of the bad LDL cholesterol and reducing your risk for a heart attack. I recommend that everyone, whether they take statins or not, should:

• follow a diet that is rich in vegetables, fruits, whole (unground) grains, beans, nuts and other seeds

• restrict or avoid sugared drinks and sugar-added foods, mammal meat, processed meat, fried foods, and refined grains (foods made from flour or white rice)

• avoid being overweight

• try to exercise every day

• keep blood levels of hydroxy vitamin D above 20 ng/dL

• avoid smoke, alcohol and recreational drugs

MARCH 1

Cyclists Age Better

Two exciting studies show that older men and women who have cycled for many years do not have the markers of aging found in non-exercising people (Aging Cell, March 8, 2018). Their muscle size and strength, amount of body fat, levels of hormones such as testosterone, and blood cholesterol levels were close to those of much younger people. Their maximal ability to take in and use oxygen was more like that of people in their twenties than in non-exercisers of their own age group. Incredibly, the cyclists’ immunity did not show the deterioration that is expected with aging. These studies focused on cyclists, but similar results would probably be found with other types of sustained exercise.

The Studies

Researchers from London and Birmingham, England, studied the same groups of people with one study concentrating on muscles and the other on the immune system. The participants were 125 amateur cyclists (84 men, 41 women) aged 55-79 years. These were not elite athletes; to qualify for the study, the men had to be able to cycle at least 60 miles in 6.5 hours, and the women, 36 miles in 5.5 hours (a moderate pace of less than 10 miles per hour for the men and 6 1/2 miles per hour for the women). All of the participants had been cycling regularly for most of their adult lives, with an average of 26 years. These cyclists were compared to 75 healthy non-exercisers aged 57-80, and 55 younger non-exercisers aged 20-36. The authors excluded all people who were smokers or heavy drinkers or had high blood pressure or medical problems.

Amazing Benefits in Immunity

With aging, the thymus gland in the front of your upper chest shrinks and progressively loses some of its ability to make T-cells that help to protect you from developing cancers and infections. The most surprising news from this study is that the thymus glands of the older cyclists produced as many T-cells as those of the young people.

T-cells recognize foreign proteins on the surface of invading germs and cancers to tell your immunity to attack and kill these cells. They then stimulate your immune system to make antibodies to attach to and kill invading germs and cancer cells, and produce chemicals called cytokines that activate other T-cells to remove germs and cancer cells from your body. Other regulatory T-cells dampen down your immunity so that your immunity does not attack and destroy your own healthy cells.

Larger and Stronger Muscles and Better Use of Oxygen

The authors took muscle biopsies from the vastus lateralis muscle in the front of the cyclists’ upper legs, the muscles strengthened most by cycling. The cyclists’ muscles did not show the expected signs of aging:

• drop in muscle size,

• drop in mitochondrial protein content, and

• decrease in ability to take in and use oxygen.

Their muscles did show a decrease in capillary blood vessel density. The cyclists’ maximal ability to take in and use oxygen, move air in their lungs, and develop muscle power (wattage) were like those of the much younger people.

Loss of Muscle Size and Strength with Aging

All people, even regular exercisers, can expect to lose muscle size and strength as they age. Researchers at the University of Guelph in Canada have offered a new explanation (Cell Reports, March 13, 2018). All muscle fibers contain many mitochondria, small furnaces that turn food into energy. However, this process of providing energy for muscle cells produces end products called Reactive Oxygen Species (ROS), also known as free radicals, that damage parts of muscle cells and are directly responsible for the loss of muscle fibers with aging. Muscles normally use another chemical called ADP to rid themselves of ROS. This study shows that everyone loses muscle fibers with aging because older muscles lose some of their ability to respond to ADP and as a result, they accumulate higher levels of ROS which cause the permanent destruction of muscle fibers with the resultant loss of muscle size and strength. However, the muscles of older regular exercisers are able to clear excess ROS far more efficiently than the muscles of non-exercisers, so they have less loss of size and strength.

Exercise Helps You to Live Longer, Even If You Already Have Heart Disease

Another new study reviewed 30 years of records of 3,307 adults who had had heart attacks or angina (pain from blocked arteries leading to the heart). Those who exercised at least a little bit were 36 percent less likely to die during the study period (J of the Am Coll of Card, March 2018;71(10)). Weight loss without exercising did not reduce their death rate. This study agrees with another study of more than 15,000 heart disease patients that also showed that exercise helps to prevent death in people who have already had heart attacks (J of the Am Coll of Card, October 2017;70(14:). Moderate activities can include walking, gardening, ballroom dancing, water aerobics or casual cycling. Vigorous exercise includes cycling faster than 10 miles an hour, jogging or lap swimming, according to the American Heart Association.

My Recommendations

These studies show that many of the accepted signs of aging come from lack of exercise, not just from getting older. Regular vigorous exercise as you age helps you to maintain healthful qualities of your younger days so that you will have a healthier and more active later life. Exercise helps to prevent disease and death, even if you have not been a life-long exerciser. Everyone should maintain a daily exercise program. It does not have to be intense to prolong your life. If you have existing health problems or questions, consult with your doctors about any limitations that may apply to you.

FEB 18

Resting Heart Rates Can Be Too High or Too Low

Your resting heart rate should average between 50 and 70 beats a minute. Athletes can have rates between 30 and 50 and still have healthy hearts, and your heart rate temporarily can go above 70 when you are sick, stressed or sleep deprived, but all people who have persistent resting heart rates greater than 70, non-athletes who have heart rates below 55, and anyone with a heart rate below 60 with heart palpitations, fainting , dizziness or other symptoms may want to check with a doctor. Resting heart rates greater than 70 are associated with increased risk for diabetes (Int J Epidemiol, Jun 2010;39(3):900–906), heart attacks, certain cancers and premature death (CMAJ, Oct 18, 2016;188(15):E384–E392).

The Research

• More than 6000 men were followed for more than 25 years. Those with resting heart rates greater than 73 beats per minute were 140 percent more likely to die from cancer than those with resting heart rates of less than 60 beats per minute (PLoS ONE, published online August 03, 2011).

• Of more than 53,000 men followed for almost 30 years, those with resting heart rates greater than 80 beats a minute were far more likely to suffer heart attacks and cancer than those with fewer than 60 beats a minute (Mayo Clinic Proceedings, 12/12/2013).

• 58 obese men and women exercised five times a week at 70 percent of their maximum heart rate for 45 minutes. In just 12 weeks they lowered their resting heart rates by five to nine beats per minute (Br J Sports Med, 2009; 43: 924-927).

• The Copenhagen Study of 3,000 men followed for 16 years found that those with a resting heart rate between 71 and 80 beats per minute were at a 50 percent elevated risk of death, between 81 and 90 beats per minute had double the risk, and resting heart rates over 90 beats per minute tripled the risk (Glob Cardiol Sci Pract, Oct 9, 2015;2015(3):33). Furthermore, high resting heart rates were associated with lower levels of physical fitness, higher blood pressure, overweight, and higher levels of circulating blood fats. The authors concluded that “a high resting heart rate is not a mere marker of poor physical fitness, but is an independent risk factor for disease.”

A High Resting Heart Rate May Predict Heart Disease

A strong heart pumps lots of blood with fewer beats, while a weak heart has to beat more often to pump the same amount of blood. A high resting heart rate may indicate that arteries are blocked or that there is heart muscle damage so the weakened heart has to pump more often to circulate oxygen to your body.

How a High Resting Heart Rate Relates to Cancer

Telomeres are the end caps of chromosomes that help to protect them from being destroyed when a cell reproduces. The longer your telomeres, the less likely you are to develop cancer, and people who exercise regularly have longer telomeres. Exercise also helps to protect the body from inflammation, a risk factor for cancer. The more intensely you exercise, the lower the heart rate and the greater the protection against inflammation.

How to Check Your Resting Heart Rate

To find out your resting heart rate, check your pulse when you first wake in the morning, before you get out of bed. You can use a heart rate monitor, a blood pressure cuff that includes a pulse check, one of the many fitness trackers that have a heart rate feature, or any watch that shows seconds. If you have a smart phone you can download a free heart rate monitor app. Set your device on your bedside table the night before so you do not have to move around when you wake up. If you are using a watch, place your fingers on the side of your neck where you feel a strong heartbeat. Count the beats for ten seconds and multiply by six. Do this for several days and take an average.

My Recommendations

A morning resting heart rate consistently over 70 is often a warning signal that you have a weak heart and may be headed for serious disease. If your resting pulse rate is over 70 beats per minute and you are not sick or taking stimulants, check with your doctor, particularly if you also have:

• LDL cholesterol greater than 100,

• blood sugar greater than 145 mg/dL one hour after eating,

• systolic blood pressure greater than 120 at bed time, or

• a C-reactive protein greater than 10 mg/L.

Athletes often have exceptionally low heart rates indicating a strong heart, but in non-athletes a low heart rate can be caused by damage to the heart’s electrical conduction system or muscle. If you have a resting heart rate of less than 60 and are not a regular exerciser, or if you are regular exerciser and have a bedtime systolic blood pressure greater than 120 or below 90, chest discomfort, dizziness or fainting, a bad LDL cholesterol greater than 100, or any possibility of an irregular heartbeat, you should check with your doctor.

FEB 12

Testosterone for Older Men

Medical journals have reported trials that examine the benefits and harms of taking testosterone for men over 65 with low blood levels of testosterone (less than 275 ng/dL). At 12 study sites across the country, a total of 790 participants were given testosterone gel or a placebo applied daily to the skin. Most of these men had low testosterone due to aging, not due to damage to the testicles or brain where testosterone levels are controlled. Over a year, investigators measured the effects of testosterone on:

• bone density and strength

• anemia

• heart health

• cognitive function

• sexual function

Bone Density and Strength: Testosterone increased bone density and strength in 200 older low-testosterone men (JAMA Intern Med, February 21, 2017). These increases were greater in the spine than in the hips.

Anemia: Testosterone raised hemoglobin levels by at least 1 g/dL in nearly 130 men with anemia (JAMA Internal Medicine, Feb 21, 2017).

Heart Health: Testosterone increased plaques significantly in the arteries leading to the heart likely to increase risk for heart attacks (JAMA, 2017;317(7):708-716). However, another study of more than 44,000 men with low testosterone showed that three years of testosterone gel reduced heart attack rate by 25 percent compared to those given placebos (JAMA Internal Medicine, Feb 21, 2017). The effects of testosterone on heart attack risk are controversial.

Cognitive Function: Testosterone did not improve memory or other brain functions including verbal memory, visual memory, executive function or spatial ability in 500 men with age-associated memory loss (JAMA, 2017;317(7):717-727).

Sexual Function: Improvement in sexual function is the benefit most strongly supported by research studies. However, having low testosterone levels does not determine whether a man will respond to erection-increasing drugs such as tadalafil in older men with enlarged prostates and erectile dysfunction (J Sex Med, May 2016;13(5):843-51).

A review of several other studies showed that testosterone gel can improve depression, bone mineral density, energy, libido, erectile function, muscle mass, insulin resistance, and lower urinary tract symptoms (Curr Opin Urol, Mar 2016;26(2):152-7). Testosterone treatment did not appear to increase a man’s risk of developing an enlarged prostate.

Testosterone Is Often Given to Men Who Will Not Benefit from its Use

A study from Baylor Medical School shows that more than 85 percent of men treated with testosterone do not have any disease caused by low testosterone. Most of the men suffer from adult-onset hypogonadism associated with chronic medical conditions such as diabetes, metabolic syndrome, arteriosclerosis and obesity. They do not have a deficiency of testosterone caused by damaged testicles or brain hypothalamic and pituitary glands that cause low testosterone. They should be treated for these conditions and not take testosterone, which may increase their risk for future heart attacks (Mayo Clinic Proceedings, June 24, 2016).

My Recommendations

• Men with normal blood levels of testosterone (>300) should not take testosterone since it may increase risk for heart attacks, liver damage and shutting down their own natural production of testosterone.

• Older men with normal testicles and brain hormones should not take testosterone unless their testosterone is very low (below 150).

• Usually men should take testosterone if they have low levels of the brain hormones that stimulate the testicles to produce testosterone or testicles that are damaged so they cannot make testosterone.

• Most men who suffer from poor sexual function because they have conditions that damage their sexuality, such as overweight, diabetes, arteriosclerosis or other life-shortening conditions that affect sexual function, should work to reverse those conditions rather than resorting to testosterone.

• Testosterone pills can damage the liver, so if a man chooses to take testosterone, the form of choice is a gel that is absorbed through the skin so it avoids the liver.