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Delayed Onset Muscle Soreness (DOMS)

To make muscles stronger, you need to exercise intensely enough to damage the muscles. You can tell that you are damaging muscles when you exercise vigorously enough to feel soreness in those muscles eight to 24 hours later, which is called Delayed Onset Muscle Soreness or DOMS.

Exercise to Prevent a Heart Attack

The same training principles that improve athletic performance in competitive athletes also help to prevent heart attacks and prolong lives. The SUN Study on 18,737 middle-aged people showed that those who exercise intensely have half the rate of heart attacks as those who do the same amount of exercise less intensely.

Exercisers Should Follow a Heart-Healthy Diet

A study of 798 asymptomatic and apparently healthy master athletes (runners, cyclists, triathletes, rowers and hockey players), 35+ years old, who exercised fairly vigorously 3-7 days a week, found that 10 percent had greater than 70 percent blockage of the arteries leading to their hearts. Exercise helps to prevent heart attacks, but exercise does not prevent plaques from forming in arteries.

Lifestyle Can Override Genes

Studies in the new field of Epigenetics are showing that lifestyle factors can change the way your body responds to your genes. In one of these studies, researchers were delighted to find a set of identical twins with vastly different lifestyles. They found that a lifetime of exercise is likely to give you the body characteristics of a healthy athlete, while an inactive lifestyle can give you body characteristics associated with increased risk for many diseases.

Weak Muscles Increase Risk for Dementia

Many studies show that having excess fat in your belly is associated with increased risk for dementia, but a new study shows that as a person ages, lack of muscle size and strength appears to be an even stronger predictor of dementia than having excess belly fat.

How Inactivity Can Cause Heart Failure

People who lie in bed without moving day after day suffer progressive weakening of their heart muscle. Eventually the heart becomes too weak to pump enough oxygen to the brain, they stop breathing and die from heart failure. A recent study on mice shows how this is likely to happen.

Lack of Vitamin D May Harm Exercisers

A study in mice suggests that having low levels of vitamin D may harm athletes and exercisers by limiting how long they can exercise. Many exercisers and competitive athletes are vitamin D deficient even if they live in the sunbelt.

Running Stride Length and Speed

Your most efficient stride length is determined by what feels most comfortable to you. You cannot run faster by consciously trying to increase your stride length. When you run, your foot hits the ground with great force. The tendons in your legs absorb some of this energy and then contract forcibly after your heel hits the ground, so you regain about 60 to 75 percent of that stored energy. When you try to take a stride that is longer than your natural one, you lose a great deal of this stored energy, tire much earlier and move your legs at a slower rate.

Should Runners and Cyclists Lift Weights?

A review of many scientific articles shows that runners and bicycle racers can run and cycle faster with added strength training because it makes them stronger, so that they can run and cycle more efficiently with less effort. However, the improvement in racing performance with added weightlifting is small, and sometimes nonexistent, because lifting weights does not improve VO2max (the ability to take in and use oxygen).

Physically Active Jobs vs Leisure-Time Exercise

A review of 17 studies, covering almost 200,000 people, found that men who work at the most physically active jobs have an 18 percent higher risk of premature death compared to people with less physically-demanding jobs. The authors did not find that women who had to keep moving at work had shortened life spans, probably because work-related physical activity for women is usually not as demanding as it is for men.

Keto Diet Not Likely to Help Athletes

A low-carbohydrate, high-fat (LCHF) ketogenic diet impairs performance in sports that require speed. On a low-carbohydrate diet, you can't train very fast and you can't move as fast in races. Your body uses primarily carbohydrates and fats, and a small amount of protein, to supply you with energy when you exercise. A ketogenic diet means that you try to get your body to use fat as the prime energy source for your muscles.

Some Health Benefits of Exercise May Come from Changes in Colon Bacteria

A six-week program of exercise markedly increased the types of healthful colon bacteria and their functions in healthy but previously sedentary people. At the end of the six-week exercise program, the lean group had more of the healthful types of colon bacteria that ferment unabsorbed soluble fiber into short chain fatty acids (SCFAs).

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

Fruit Beats Sports Drinks for Exercisers

Many studies show that you can exercise longer and more intensely and recover faster when you take a source of sugar during vigorous exercise. Dozens of brands of sports drinks are promoted to fill this need, but a new study from Appalachian State University shows that a banana appears to offer superior results, specifically helping athletes to recover faster from intense exercise.

How Exercise Reduces Dementia Risk

Almost 50 percent of North Americans over 85 and 13 percent of those over 65 suffer from Alzheimer's disease (Alzheimer's Assoc Facts and Figures, 2018). We know that you lose brain cells as you age, and scientists used to think that you could not make new brain cells. However, an exciting new study from Columbia University suggests that you can make new brain cells as you age, and that loss of brain function may be caused by lack of adequate blood flow and nourishment of brain cells.

Good News for Male Cyclists

Cycling is not associated with increased risk for impotence or urinary symptoms. The largest and best study on the subject to date shows that serious cyclists are no more likely to suffer impotence or urinary problems than swimmers or runners.

Cyclists Age Better

Two exciting new 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. 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.

How Exercise Helps to Prevent Diabetes and Heart Attacks

Everyone should try to exercise every day because exercise helps to prevent diabetes and heart attacks by lowering high blood sugar and stabilizing plaques. A review of 12 studies shows that exercising within three hours after eating lowers blood sugar levels significantly because contracting muscles remove sugar from the bloodstream at a very high rate and don't even need insulin to do so.

Intervals for Everyone

The American College of Sports Medicine (ACSM) surveyed more than 4,000 fitness professionals and found that High Intensity Interval Training (HIIT) is the most popular trend in fitness for 2018. All healthy people can benefit from some form of interval training. They can pick up the pace for a few seconds while walking, running, cycling, swimming, skiing or skating, and then slow down when they feel the least discomfort.

Cold-Weather Exercise Tips

You feel cold most in your fingers, ears and toes. To help keep your hands warm on very cold days, wear an inner layer of thin gloves made from loosely-woven material that permits sweat to pass through. Gloves allow you to control your fingers better than mittens when you shift gears or use ski poles.

Strength Training May Reduce Deaths from Heart Attacks and Cancers

You can expect to lose muscle size and strength as you age. Between 40 and 50 years of age, you lose more than eight percent of your muscle size. This loss increases to 15 percent per decade after age 75. The people who lose the most muscle usually are the least active, exercise the least and are the ones who die earliest.

Low Vitamin D Increases Risk for Injuries

A study of 214 prospective National Football League players found that 73 percent of those who were deficient in vitamin D had a severe lower leg injury when they played in college, compared to only 40 percent of those who were not deficient in vitamin D (Arthroscopy, Dec. 21, 2017). Eighty-six percent of those who missed college games because of lower leg injuries were vitamin D deficient.

Exercise Promotes Good Gut Bacteria

Good bacteria that live in your gut can help to keep you healthy, while the bad colon bacteria increase your risk for heart attacks, strokes, diabetes, certain cancers and autoimmune diseases. Researchers have focused mainly on how diet affects the growth of good and bad gut bacteria, but now two new studies show that exercise encourages the growth of good bacteria in your colon and reduces the number of bad ones.

Mitochondria and Gut Bacteria Work Together for More Endurance

Endurance training for six weeks in humans and mammals has been shown to increase mitochondrial content from 30 to 100 percent and volume density up to 40 percent (Front Physiol, May 19, 2017;8:319). This fascinating study shows that the exercise-induced increase in available energy markedly increases the growth of the types of good bacteria in the colon that need more energy.

Sarcopenia (Muscle Loss with Aging) Linked to Inflammation

Recent research shows that we can now add sarcopenia, loss of strength and muscle size with aging, to the list of medical problems associated with inflammation. Older people who suffer from sarcopenia are far more likely to have high blood levels of the markers of inflammation such as CRP, SED rate and adiponectin.

Too Much Exercise?

Countless studies have shown that exercise helps to prevent heart attacks, but some researchers have found scarring in heart muscle and increased plaques in the heart arteries of men who have run many marathons and triathlons, resulting in news headlines warning of "too much exercise."

Flat Feet, Pigeon Toes and Bow Legs

Many of the world's great sprinters have flat feet. Most football coaches can pick their halfbacks just by watching them walk. The fastest runners are often flat footed, pigeon toed and bow-legged.

Exercise May Help to Prevent Dementia

More than 80 percent of North Americans over the age of 85 suffer from some form of dementia. A new study in rats helps to explain why exercise could help to prevent or delay this dreaded condition (Sci Rep, 2017 Sep 7;7(1):10903). A group of rats were kept in cages that had exercise wheels,...

Principles of Training

You will not become more fit by doing the same training regimen every day. Athletes train by taking hard workouts on one day, feeling sore on the next, and not taking another hard workout until the muscles stop feeling sore.

NSAIDs May Block Gains in Endurance and Strength

A new study io mice showed that taking NSAIDS (Non-Steroidal Anti-Inflammatory Drugs), to reduce muscle pain before, during or after exercise, can reduce the gains in endurance from aerobic training.