Growth Hormone Does Not Prevent Loss of Muscle Strength

As you age, expect to lose muscle fibers and strength unless you exercise. A study from the University of Florida in Gainesville shows that a program of exercise training later in life helps aging rats to reverse this age-related loss of muscle size and strength (American Journal of Physiology: Regulatory, Integrative and Comparative Physiology, November 14, 2007). The study also showed that short-term administration of growth hormone late in life does not prevent loss of muscle strength. Previous studies show that it may help people get rid of fat.At this time, there is not enough evidence for an older person to take growth hormone to improve muscle strength, and there is no long-term data on safety. Sudden deaths reported in athletes who...

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Job Fatigue? Carb Snacks Can Help

If you have a physically demanding job that keeps you moving all day, you may have greater endurance if you eat small snacks throughout the day instead of having a single large meal at lunchtime. Researchers at the University of Montana in Missoula showed that snacking on carbohydrates may prolong your endurance during a long day of continuous movement. They asked men and women to exercise intermittently for ten hours. Each hour, they performed nine minutes of upper-body weight lifting, 19 minutes of cycling, and 20 minutes of walking on a treadmill, with a one-minute rest between each exercise. This was followed by a 10-minute rest and feeding period. Those who took carbohydrates every hour were able to keep more sugar (glycogen) in their...

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Longevity Linked More to Fitness than Weight

Being in shape helps to prolong your life, even if you are overweight and even if you store fat primarily in your belly, which is a major risk factor for diabetes, heart attacks, and probably certain types of cancers (JAMA, December 5, 2007). As people age, most gain weight and become progressively less active. Researchers at the University of South Carolina in Columbia showed that a person's fitness level was a far stronger predictor of premature death than body fat. Those who were fit suffered less than half the death rate of those who were out of shape. They also showed that those who store fat primarily on their bellies are at significantly greater risk for dying early and that people with abdominal obesity who exercise are far less likely...

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Intestinal Bacteria May Cause Weight Gain

Why are some people skinny, even though they eat large amounts of food, while others become fat? Jeffery Gordon of Washington University in St. Louis thinks it's because some people have types of bacteria that cause them to absorb more calories from their food.You have two absorption systems in your body. You absorb most of your food as it passes through your small intestines. Food that is not absorbed in the small intestine goes to your colon. The colon contains a huge colony of bacteria that work to ferment undigested carbohydrates such as soluble fiber into short chain fatty acids and simple sugars that can then be absorbed through the colon walls into the bloodstream. Most people get about ten percent of their total calories from food absorbed...

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Clementines: Healthful Snacking and More

Clementines are the small citrus in boxes or mesh bags that appear in markets during the winter months. This year's crop is tasty, juicy and plentiful (prices are low!). They're great for snacking, dessert or in fruit salads. Clementines also make a wonderful addition to almost any green salad. Or try Diana's Recipes Using Clementines.In Canada and perhaps elsewhere clementines may be called mandarins. Technically clementines are a cross between mandarins (Citrus reticulata) and Seville oranges (Citrus auratium). Recipes using clementines can be made with any of the tangerine-sized citrus or with oranges sections cut into bite-size pieces.To prepare clementines for salads, just peel and section. If they are large or you want more flavor from...

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Lactose Intolerance: How to Eat Healthfully

Fifty percent of North Americans are lactose intolerant. They lack the enzyme to split the double sugar, lactose, found in milk and other dairy products. Since you can only absorb single sugars, if you can't split the double sugar, it passes to your large intestine where it is attacked by bacteria and fermented, causing gas and cramping. Some people deal with this by adding the lactase enzyme to their diet. You can eliminate all dairy products and still have a perfectly healthful diet. Yes, milk is a good source of calcium, vitamin D, protein and other nutrients, but it is far from essential. You can get all the calcium you need from a variety of other foods.Many doctors, dieticians and vegetarians oppose the use of dairy products, and back...

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Wound Healing Time Increases with Age; Exercise Can Help

Animal studies suggest that exercise may be even more important for older people than for younger ones. A report from the University of Illinois at Urbana-Champaign shows that exercise significantly decreased wound size and increased healing rate in older mice. However, exercise had little effect on the rate of wound healing in young mice. (American Journal of Physiology - Regulatory, Integrative and Comparative Physiology, November 14, 2007).Mice ran on a treadmill at moderate intensity for 30 minutes a day for eight days. They then were given four full- thickness skin wounds and the rate of wound healing was checked daily for 10 days. Compared to age-matched non- exercising mice, the older exercisers healed faster.The leading theory is that...

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Stretching: Know When, How and Why

Stretching the leg muscles improves muscle flexibility and strength, running speed, and jumping distance, according to a study from Louisiana State University. Stretching elongates muscles and tendons. Longer tendons allow muscles to exert a greater torque on the joint to exert more power to help you lift heavier, jump higher and run faster.However, other studies show that you should not stretch before a competition involving speed and strength. The longer the athletes stretched, the weaker they became. Prolonged stretching fatigues muscle fibers so that they contract with reduced force. Do slow deliberate stretches lasting a few seconds to several seconds, rather than rapid hard pulls on your muscles that can tear them. Stretching cold muscles...

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Athletes Harm Others with Performance Enhancing Drugs

Some people think that we should let athletes take performance-enhancing drugs because they think that these athletes can only harm themselves and do not harm others. We already know that anabolic steroids can cause liver damage, heart attacks and strokes, and that growth hormone causes heart attacks by causing the heart muscle to outgrow its blood supply. Now a two-year study of former East German athletes shows that athletes who take these drugs can harm their children.In the 1970s and 80s, almost all government sponsored East German athletes were forced to take anabolic steroids and other performance-enhancing drugs. A study of 69 children of 52 of these athletes showed that seven had birth defects and four were mentally retarded, an unusually...

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Mental Fatigue from Low Blood Sugar Levels

Exercisers and athletes can expect to feel fatigued when their blood sugar levels drop. Researchers at Loughborough University, UK showed that athletes who did not take sugar during soccer competition lasting 90 minutes felt more tired, had less competitive desire, and had far lower blood sugar levels than athletes who took a sugared drink every 15 minutes during their game. Your brain gets more than 98 percent of its energy from sugar in the bloodstream. However there is only enough sugar in the bloodstream to last about three minutes. The liver must constantly release sugar into the bloodstream, but there is only enough sugar in the liver to last eight hours during rest and far less than that during exercise. So athletes who do not take...

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Angioplasty Patients Can and Should Exercise

If you have had angioplasty and your doctor does not already have you in as supervised exercise program, ask when you can start. In one study from Bern, Switzerland, researchers showed that a three-month exercise program can increase blood flow to the heart in people who already have their coronary arteries blocked by plaques (European Journal of Cardiovascular Prevention and Rehabilitation, April 2007). The study participants were selected from patients who had stents inserted to widen blockages in their coronary arteries. The longer and harder the subjects were able to exercise, the greater the increase in blood flow.The blood flow to the heart muscle comes primarily from arteries on the outside surface of the heart. Chest pain with exercise...

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Smarter Baseball Players Live Longer

Smarter baseball players live longer, according to researchers at the Department of Economics at Shippensburg University in Pennsylvania. The authors collected data on players who were born between 1945 and 1964 and found that the death rate for players who attended only high school was almost twice as high as those who went to college. They also found what high body fat levels were associated with premature death. The study was published in the journal Death Studies. The good news for all athletes is that the baseball players had only 31 percent of the death rate of the general population. The lower death rate in the more highly educated players is probably due to their increased awareness of life style factors linked to premature death,...

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Small Lifestyle Changes Combat Obesity in Children and their Families

Pediatricians at the University of Colorado at Denver have shown that very small changes in lifestyle can help stem the epidemic of obesity in North American children. Families of overweight children, seven to fourteen years of age, were asked to make two lifestyle changes: 1) to walk an additional 2000 steps per day, as measured by pedometers, and 2) to eliminate 100 calories per day by replacing a source of dietary sugar with a non-caloric beverage or sweetener. At the end of the six-month trial, most of the children had lost weight and the parents had no significant weight gain. Journal referenceObesity comes from eating too much and exercising too little. It is associated with increased risk for heart attacks, strokes, kidney failure, certain...

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Orthotics may relieve foot pain from running or exercising

People with high arches are at increased risk for foot pain and stress fractures of their bones of their feet because their feet are usually very poor shock absorbers. A report in Cochrane Database of Systematic Reviews (October 2007) shows that custom orthotics can help. When you run rapidly, your foot hits the ground with a force equal to about three times body weight. This force can break bones and damage muscles, nerves, and tendons. So most people land on the outside bottom of their feet and roll inward. This is called pronation which helps absorb some of the shock of the foot striking the ground. However, pronation can cause pain from stretched ligaments (plantar fasciitis), pulled tendons (tendinitis), or pinched nerves (neuromas). Some...

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Muscle Cramps from Exercise: Causes and Prevention

Exercisers are often told that muscle cramps are caused by lack of salt (sodium) or low potassium. However, recent studies show that athletes in endurance events who suffer cramps usually have normal sodium and potassium levels. A review of the current literature from Buenos Aires, Argentina shows that doctors don't know very much about exercise-induced muscle cramps. The most common cause appears to be muscle damage. Athletes may be able to prevent cramps by slowing down when they feel the muscle pulling and tightening, and picking up the pace only when the muscle feels good again. Journal referenceCramps may occur as a side effect of drugs used for high cholesterol, high blood pressure or diabetes. Oral contraceptives, various other drugs...

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Measurable Fat Loss from Exercise

If you weigh yourself before and after an hour or two of exercise, the difference is likely to be fluid loss. However, in events lasting several hours or even several days, measurable fat loss can occur. At a competitive 12-hour indoor stationary bicycle marathon, one athlete took fluids and food throughout the entire competition, and still lost 2.64 pounds. Of this weight loss, 1.98 pounds was due to loss of fat. His calculated muscle weight increased by 1.46 pounds due to damage to the muscle cells, which results in fluid retention in the cells. Journal referenceDuring vigorous cycling, an athlete can burn between 600 and 1000 calories per hour, so this cyclist probably used more than 9000 calories in his 12-hour event. That is equal to...

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Saunas May Benefit Athletes and Exercisers

For many years I have believed that heating muscles in a hot tub or sauna after exercise interferes with muscle contractions and hampers muscular endurance. However, a study from the University of Otago in New Zealand shows that taking a sauna after workouts for three weeks helped athletes to exercise longer to exhaustion.Trained runners sat in a humid sauna for 30 minutes at 89.9 degrees centigrade immediately after exercising, 12 times in three weeks. They then ran as hard as they could on a treadmill for about 15 minutes, to exhaustion. Sauna use increased run time to exhaustion by 32 percent, which would equal an improvement of approximately two percent in a full-length endurance time trial. Their blood volumes increased by more than seven...

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Exercise More Important than Weight Loss for Diabetes Prevention

Exercise is even more important than weight loss for prevention or control of diabetes, according to a report from the Australian National University in Canberra. Dr. Richard Telford concludes that obesity is associated with, but does not cause, diabetes, heart disease and premature death. The health benefits of exercise include increasing cells' ability to respond to insulin, lowering blood sugar levels, and preventing all the side effects of diabetes. Weight loss is not necessary for a person to gain these benefits from an exercise program. Journal referencesMost cases of Type II diabetes are caused by the body's inability to respond to insulin. Strengthening muscles makes cells more responsive to insulin. Your ability to respond to insulin...

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Caffeine May Prevent Dementia

Caffeine may protect against loss of memory or thinking skills in older women, according to a study published in Neurology. The researchers studied cognitive decline, dementia and caffeine intake of 4,197 women and 2,820 men aged 65 and over in three French cities for four years. They tested the participants' cognitive skills at the start of the study and again at years two and four.The results showed that compared to women who drank only one cup a day or less, women who drank three or more cups of coffee or tea a day had a 33 per cent reduced risk of decline in verbal retrieval over the four years. The protective effect of caffeine appeared to increase with age, rising from a 27 per cent reduced risk for women aged 65 to 74, to 70 per cent...

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Blood Sugar Levels Affected by Activity

How foods affect blood-sugar levels varies from person to person and from one time to another in a single individual. For example, if you eat a jelly donut in the evening, your blood sugar may rise well over 200 (it should never be higher than 160). If you eat the jelly donut when you have been riding your bike for an hour, your blood sugar level may not rise at all.Researchers at University Medical Center in Utrecht, the Netherlands showed that eating sugar and flour markedly increases risk for heart attacks in middle-aged women. Being overweight increased the risk even more. More than 15,000 healthy Dutch women, ages 49-70, were followed for nine years. They suffered 556 cases of coronary heart disease and 243 strokes. The ones most likely...

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Longer Lower Legs Benefit Runners and Walkers

People who have longer lower leg lengths (the distance from knee to ankle) will usually have greater endurance during running or walking than those with shorter lower leg lengths. In a study reported in the Journal of Human Evolution, researchers at the University of Wisconsin showed that people with longer lower legs use less energy when they run.In a previous paper in the same journal, these authors showed that people with longer lower legs are better able to prevent heat build-up, which slows you down and makes you tired. When you exercise, almost 80 percent of the energy that you use to power your muscles is lost as heat. So the harder you exercise, the more heat you produce and the harder your heart has to work to get rid of the extra...

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Protein: How Much Do You Need?

The Recommended Allowance for protein for most people is about 70 grams per day. Many types of foods contain protein, and it is easy to meet your protein requirements with a typical varied diet. For example, you would meet your daily requirement for protein if you ate two of cups each of beans and whole grains such as barley, brown rice or oatmeal, three ounces of tuna, and two glasses of milk or a vegetarian milk substitute. If you are not sure whether you eat enough protein, keep track by checking the labels of the foods you eat for a few days. You will probably find that you get plenty of protein without any special effort. Protein is made up of protein building blocks called amino acids. Your stomach acids and enzymes in the stomach and...

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Restaurant Meals Can Be Healthful

Everyone can enjoy an occasional meal in a restaurant without worrying about the consequences. But if you have to eat in restaurants several times a week, you need to devise ways to make healthful choices and avoid the temptation to over-eat. If you are trying to control weight, diabetes, cholesterol or high blood pressure, you must find ways to meet your special requirements.First, choose restaurants that gives you a fighting chance. Find a restaurant with a good salad bar and load up on fresh vegetables. Order broiled fish for your entree. Ask to have it prepared with lemon juice instead of butter. Have steamed vegetables as an accompaniment, without added butter, and fresh fruit or fruit ice for dessert.Asian restaurants often have a wide...

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Walking to Lose Weight: Miles Less Important than Intensity

For exercise to help you control weight, you must exercise fairly intensely or else you need to exercise for many hours, and most people do not have the time to exercise for three or four hours or more every day. A study from the University of Massachusetts in Boston shows that middle-aged women who exercise at very low intensity are fatter and gain weight far more easily than women who exercise more intensely. Journal referenceThis is what you would expect. When you exercise intensely enough to raise a sweat, you can increase your metabolism and continue to burn extra calories for several hours after you stop exercising. When you exercise at very low intensity, you do not increase your metabolism and you have to exercise for a very long time...

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Sugar Helps You Exercise Longer

Bicycle racers in long events such as the Tour de France take sugar supplements while they ride to increase their endurance. If you plan to exercise for more than two hours, you can help yourself last longer by taking a source of sugar after 30 minutes and several times more throughout your event.When you exercise, you convert food to energy for your muscles by stripping off electrons and hydrogen from the foodstuffs. This process manufactures a chemical called ATP that provides energy that does not require oxygen. A study from the University of Waterloo in Ontario, Canada shows that taking sugar during prolonged exercise raises levels of ATP. At exhaustion, ATP levels were at the same low levels in both the group taking sugar and those taking...

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Build Aerobic Capacity by Strengthening Leg Muscles

Aerobic capacity is a measure of your ability to use oxygen to do work. If your body can process more oxygen than that of another person, usually you will be able to run faster, walk or work longer, and have more energy than that person.The loss of aerobic capacity with aging explains why older people cannot compete effectively against younger ones in endurance events. The good news is that a regular exercise program can help you compensate for this loss by strengthening skeletal muscles and increasing your maximum heart rate. Tasks that you did without effort when you were younger can become major ordeals that leave you exhausted when you are older. It takes more effort and time to walk up stairs, mow the lawn, fix a faucet or wash the dishes....

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How Vitamin D Helps to Prevent Cancer

Many recent reports show that vitamin D is far more than just a hormone that strengthens bones. It is necessary for maintaining a healthy immune system. Every day, your body produces millions of cancer cells, and your immunity is supposed to search out and destroy these cells. However, when you lack vitamin D, your immunity is less able to destroy cancer cells. A study from Creighton University in Omaha, Nebraska, showed that women had a 77 percent lower rate of cancer in the second through fourth years of taking calcium and vitamin D pills than women taking placebos. Journal referenceThe only really rich food source of vitamin D is fatty fish. Very few people are able to meet their needs for vitamin D from the foods that they eat and have...

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High Resting Heart Rate: Common Causes

If your resting heart rate is greater than 70, check with your doctor to see if your thyroid is overactive, you are anemic, or you have an infection, hidden tumor, a weak heart or other cause of a rapid heart rate. Having a resting heart rate greater than 70 increases your chances of suffering a heart attack. Journal referenceAt this time, there is not enough solid data to show that taking drugs to slow heart rate, by itself, will help to prevent heart disease when no cause is found. However, those with chest pain during exercise or blocked blood flow to the heart do benefit from drugs to slow heart rate. Several ongoing studies are trying to determine if all people with heart rates over 80 should take drugs to slow heart rate. Drugs that can...

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Interval Training to Improve Performance in Sports

The faster an athlete moves in training, the faster he or she will be able to move during competition. So athletes use a training technique called interval training in which they run, cycle, skate, ski or swim very fast for a short time. When they become severely short of breath, they slow down until they recover, and then move very fast again. Researchers at Ithaca College showed that athletes can gain as much by doing this type of intense interval training on consecutive days as on alternate days (Medicine & Science in Sports & Exercise, September 2007).Interval training causes considerable muscle damage, so it usually leaves athletes sore the next day. Most trainers recommend exercising at a slower pace until the soreness disappears....

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Bicycling Tips for Blog Action Day

For Blog Action Day, here are some tips for better bicycling. You'll feel virtuous every time you ride your bicycle instead of driving your car! All cyclists should learn to pedal at a fast cadence, whether you are an experienced racer or a novice recreational rider. Muscle fatigue and damage are caused by excess pressure on the pedals, not by how fast you pedal. Pedaling at a faster cadence with less pressure allows you to pedal longer and harder. However, several researchers have expressed concern that pedaling very fast could decrease blood flow to muscles and thus decrease athletic performance. A study from Kansas State University shows that pedaling fast does not decrease a muscle's flow of blood or ability to extract oxygen from the...

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Ski Better By Preparing Now

If you love to ski, it's time to think about getting ready. The best way to train for skiing is to ski, but snow isn't always available. To prepare for a ski trip, you need to strengthen both your heart muscles and your skeletal muscles. You can strengthen your heart for skiing with any exercise that will raise your heart rate for at least 10 minutes, three times a week. However, to prepare your muscles for skiing, you have to use activities that use your upper legs, such as skating or riding a bicycle. The average bicycle rider is far better prepared for skiing than the average runner. Many joggers who can easily run ten miles find that they can't ski very long because their upper leg muscles tire and hurt after just a few minutes of skiing.You...

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Sorbitol: Poison in Your Body, OK in Foods

When blood sugar levels rise too high, sugar sticks to the surface membranes of cells. The sugar, glucose, is converted into another sugar, fructose, and eventually to sorbitol, which destroys the cells. This cell damage leads to heart attacks, strokes, blindness, deafness, kidney damage and the other harmful effects of diabetes.The same chemical is harmless when it is used in foods because you do not absorb it. Sugar alcohols such as sorbitol, mannitol or xylitol have almost the same chemical structures as carbohydrates, but they have an alcohol end on one side. This prevents them from being absorbed from your intestines, so they can be used to sweeten food without contributing any calories. The sugar alcohols pass undigested to your colon...

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Muscles Can Be Strengthened at Any Age

You are never too old to enlarge and strengthen your muscles. A study from Copenhagen, Denmark shows that just 12 weeks of lifting weights significantly strengthened the muscles of men 85 to 97 years of age (Scandinavian Journal of Medicine & Science in Sports, August 2007). After 12 weeks of training, the cross sectional circumference of their quad muscles in the front of their upper legs increased by 10 percent, and muscle strength increased by 35 to 50 percent. Furthermore, the muscle fibers that are used for strength and speed increased significantly.Frailty in old age is caused by lack of exercise, not just by growing old. With aging, you lose nerves. Each nerve is attached to a single muscle fiber, so as you lose muscle fibers you...

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Caffeine, Exercise Help to Prevent Skin Cancer

High doses of ultraviolet light damage the DNA in skin cells. Normally, damaged cells commit suicide by a process called apoptosis, so that they do not become cancerous. However, damaged cells that do not undergo apoptosis live to become cancerous. A report from Rutgers University showed that exercise and caffeine help to prevent skin cancer. Researchers divided mice into four groups: 1) inactivity, 2) exercise, 3) caffeine and 4) exercise and caffeine. Then all of the mice were exposed to high doses of ultraviolet B light that damaged their skin cells. Caffeine caused a 95 percent increase in apoptosis, exercise caused a 120 percent increase, and those who both exercised and took caffeine had a 400 percent increase in apoptosis.Cells in your...

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Tapering for Athletes and Ordinary Exercisers

Tapering refers to the period just before a major race or game, when an athlete reduces workload to be in peak shape on the day of the competition. Ordinary exercisers can apply this training principle when they plan to enter a local race or charity event.Top athletes must spend a tremendous amount of time training to be able to compete successfully. Their huge volume of work leaves them near exhaustion and before major competitions, they have to find the best way to reduce fatigue while retaining fitness. Many studies have been done to help athletes and coaches decide on the best strategy. Researchers at the University of Montreal compiled the results of 27 scientifically acceptable studies. They concluded that the best duration of tapering...

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Obesity Contributes to Vitamin D Deficiency

Lack of vitamin D can cause osteoporosis, diabetes, heart disease, degenerative arthritis, infertility, autoimmune diseases, and cancers of the breast, prostate, colon or skin. Sunlight is the best way to meet your needs for vitamin D, but dermatologists have been telling us for years that sunlight can cause skin cancer. Increased use of sunscreens use may have had the unwanted side effect of widespread vitamin D deficiency. The rise in obesity may also be contributing to increased rates of vitamin D deficiency. Once vitamin D gets into fat cells, the fat cells hold on to that vitamin so tightly that it is not easily released into the rest of the body to do its job. Furthermore, vitamin D lowers blood levels of leptin, a hormone released by...

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Rest Periods Probably Do Not Increase Weight Loss

Researchers at the University of Tokyo claim that they have shown that intermittent exercise will help you to lose more weight than continuous exercise at the same intensity. Seven men participated in three different trials: 1) one hour at an intensity equal to 60 percent of maximum oxygen uptake; 2) 30 minutes at the same intensity followed by a 20-minute rest, followed by 30 more minutes of exercise at the same intensity; and 3) one hour of rest. The trial with two bouts of 30 minutes separated by a 20-minute rest burned the most fat. This intermittent exercise trial resulted in higher blood free fatty acid, glycerol and epinephrine levels, and significantly lower values of insulin and glucose.If these researchers are correct, scientists...

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Prevent Weight Gain with Exercise: How Much is Enough?

Most people could eat all they want and not gain weight, but they would have to do a lot of exercising to accomplish this. A study from Zurich shows that it takes at least five hours per week of vigorous exercise to avoid gaining weight with aging (Revue Suisse de Médecine Praxis, May 2007). They showed that the average Swiss recreational cyclist, aged 55 to 77, has gained almost two pounds per decade from youth, compared to the non-exercising males in the same age group who gained four pounds per decade. The rate of overweight among these year-round cyclists increased from 7.4 percent in their youthful days to 25 percent by the time they reached their fifties.If you are in an exercise program and are still gaining weight, you need to exercise...

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High Fructose Corn Syrup May Be Harmful: New Evidence

The food industry continues to insist that there is no difference between high fructose corn syrup (HCFS) and table sugar, but researchers at Rutgers University have a different opinion. They have found new evidence that soft drinks sweetened with (HFCS) cause tissue damage and may contribute to the development of diabetes, particularly in children. Chi-Tang Ho, Ph.D., and his colleagues conducted tests of eleven carbonated beverages containing HFCS. He found "astonishingly high levels of reactive carbonyls" in those beverages. These highly-reactive compounds associated with "unbound" fructose and glucose molecules are believed to cause tissue damage. Reactive carbonyls are not present in table sugar, whose fructose and glucose components are...

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Arch Height Should Guide Choice of Shoes for Running or Exercise Walking

Check the height of your arches when you shop for new running or walking shoes. If you have high arches, you usually need shoes with good shock absorption. If you have low arches, you will probably benefit from shoes with good motion control (Gait & Posture, July 2007).When you run, you land on the outside bottom of your foot and roll inward. This is called pronation, which helps to protect you from injury. If you landed on your foot and did not roll, the force of the impact would be transmitted up your leg to increase your chance of breaking bones and tearing muscles. However, as you roll in from the outside bottom to the inside bottom of your foot, you will see that your lower leg twists inward. Excessive pronation twists your lower leg,...

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Air Pollution Should Not Keep You From Exercising

It's healthful to exercise and harmful to breathe polluted air, so how can you decide whether you are doing more harm than good? The worst time for pollution is when clouds cover the sky and automobiles fill the roads. Automobile exhaust fumes are the principal source of air pollution in most cities, and overlying clouds increase pollution. Usually the sun's rays heat the ground to warm air closest to the ground. Hot air rises, taking large amounts of pollutants skyward. On air inversion days, the clouds prevent the sun's rays from getting through to the ground, so the air near the ground is not heated, remains colder and doesn't rise, causing the air with its pollutants to remain close to the ground.Air pollutants such as carbon monoxide,...

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Portion Sizes Do Matter

Whether or not you are overweight, portion sizes of food are a major factor in determining how much you eat. In a recent study, researchers at Pennsylvania State University in University Park measured how much normal and overweight people ate (Obesity, June 2007). They then fed these people fifty percent larger portions of food at every meal. Both overweight and normal weight people increased their intake of food equally and they continued to eat far more food for the duration of the study.You might expect that when people overeat, they would eventually reach a point where they feel full and stop taking in too much food. However, this has not been shown to be the case. When people are offered large portion sizes, they continue to eat more food...

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Repetition Makes Muscles More Efficient

Training is specific, so the more you practice your sport, the better you are able to do it. That's why triathletes who compete and train in three sports are relatively mediocre in each sport when compared to those who only run, cycle or swim. (Sports Biomechanics, Volume 6, Issue 1, 2007). In this study, elite cyclists produced significantly more effective force on their pedals than triathletes. They had far less wasted side-to-side motion, and they required less oxygen to do the same amount of work.Repeating the same motion over and over causes your muscles to become more efficient so they can generate more power with less oxygen. For example, when you run, you use your arms to maintain your center of gravity. When your right leg moves forward,...

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Muscles Cannot Become Fat

Some people believe that if they build muscles and then stop exercising, the muscles will turn into fat. This is not a reason to avoid exercise, because muscles can't possibly turn to fat. When you exercise, your muscles become larger and stronger because exercise causes extra protein building blocks, called amino acids, to deposit in muscles. All day long, amino acids pass from your muscles into your bloodstream and then back into muscles. Exercise is the major stimulus to force amino acids back into muscles. When you stop exercising, fewer amino acids go into your muscles so the muscles get smaller. Your body has no way to store extra protein, so amino acids that are not used in your muscles are picked up by your liver, which uses them for...

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Reduce Oxidants Instead of Taking Antioxidants

Instead of taking antioxidants, researchers now think you should aim to prevent your mitochondria from making excessive amounts of oxidants. The cells of your body have tiny chambers in them called mitochondria that help convert food to energy. When they do this, they knock of electrons from nutrients, and these extra electrons eventually end up attached to oxygen. Electron-charged oxygen, called reactive oxygen species or free radicals, then attach to the DNA cells to damage them and shorten your life.At this time, scientists have found only one practical way to reduce the amount of oxidants produced by mitochondria: exercise. Vigorous exercise helps the mitochondria burn food more cleanly with the production of fewer oxidants. The same effect...

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Partial Knee Replacement: Less Pain, but Not for Everyone

The ends of bones are soft, so they must be covered with a thick white gristle called cartilage. Many people suffer from knee pain because the cartilage is damaged. They may have osteoarthritis in which the cartilage wears away, or they may have damaged cartilage in an accident or by playing sports. Once damaged, cartilage can never heal; the person spends the rest of his life losing cartilage until the cartilage is completely gone and the knee hurts 24 hours a day.Until recently, the only effective treatment has been to cut out the ends of the bones of the knee and replace the entire knee joint. Now for some people, a simpler procedure may be effective: partial knee replacement, called unicompartmental knee arthroplasty. The surgeon removes...

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Awkward Running Form Can Be Improved

Many people look terribly uncoordinated when they run. Telling them to change their form will just make them more uncoordinated. If a coach criticizes a team member for poor running form and doesn't correct the underlying causes, the person is likely to become self-conscious about how he or she looks, and run even more slowly. Coordination usually improves just with repeated practice in the chosen sport.Running form can improve markedly if you can correct muscle imbalances and structural abnormalities with appropriate exercises and perhaps mechanical devices. A coach can videotape the athletes while they run, then review the tape in slow motion to analyze the mechanical defects. For example, leaning forward during running is often caused by...

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Finger length may indicate athletic ability

High levels of the male hormone, testosterone, cause the fourth finger of unborn children to grow more than the second. This explains why men usually have proportionately longer fourth fingers than women do. Scientists can use the length of the fourth finger to tell which women were exposed to higher levels of testosterone before they were born. Researchers at the University of Central Lancashire in Preston, England showed that women whose fourth finger is much longer than their second were faster cross country runners in races of one to four miles (American Journal of Human Biology, May-June 2007). The finger length was measured from the bottom crease where the finger joins the hand to the tip of the finger. Men are typically bigger and stronger...

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Most common cause of muscle cramps: lack of salt

The most common cause of muscle cramps in exercisers is lack of salt, according to a report from the University of Oklahoma. The authors cite studies of tennis and football players showing that crampers tend to be salty sweaters, and of triathletes who cramp losing more salt during a race than peers who did not cramp. They found that intravenous saline can reverse cramping, and that more salt in the diet or in sports drinks can help to prevent heat cramping.Until now, the leading theory was that most cases of muscle cramps in competitive athletes are caused by an exaggerated "stretch reflex". When you stretch a muscle, it pulls on its tendon. Stretch reflex nerves in that tendon send a message back to the spinal cord (not the brain), and then...

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Acne patients improve on low-glycemic-index diet

Most dermatologists tell their patients that diet has nothing to do with acne, but researchers at RMIT University in Melbourne, Australia presented a paper showing that an experimental low glycemic–load diet helps to improve acne. After 12 weeks, those on the special diet had lower acne lesion counts, lower body weight and lower blood levels of male hormones, compared to those who were not on the special diet.Acne is a skin disease in which a person's skin glands produce excessive amounts of oil that is converted from a colorless liquid to a more solid white sebum. Then the body causes an immune reaction that causes redness and swelling around the oil glands on the surface of the skin. High levels of male hormones increase oil secretion, while...

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Fish Oil Supplements Can Raise LDL Cholesterol

Nobody really knows whether fish oil supplements prevent heart attacts as effectively as eating fish. However, both eating fish and taking fish oil pills can lower triglycerides and prevent clotting, which may help prevent heart attacks. Heart attacks occur when a plaque breaks off from the wall of arteries leading to the heart and travels down the ever-narrowing artery until it stops and forms a clot that blocks blood flow to the heart.A recent report shows that nine grams of fish oil supplements per day may not be completely safe because they can cause a substantial rise in the bad LDL cholesterol (from 106 to 186) that increases heart attack risk (The Annals of Pharmacotherapy, July 2007). Fish oil supplements lower triglycerides by reducing...

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Injuries more likely if you have only one sport

Triathletes are injured only about one third as often as marathon runners even though they do far more work in their program of swimming, cycling and running. Training intelligently for three sports is less likely to injure you than training very hard for one. Training is limited by damage to skeletal muscles. Every time you exercise, your muscles develop small tears with bleeding. It takes at least 48 hours for muscles to heal from exercise. Each sport stresses a particular group of muscles most. Marathon runners who train every day stress the same muscles and do not allow adequate time to recover from the previous day's workout, so they are at increased risk for injury.Top triathletes train in different sports on consecutive days. Running...

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Does High Fructose Corn Syrup Cause Obesity?

For the last 25 years, soft drinks have used high fructose corn syrup as their major form of sweetening. This coincides with a major increase in obesity in America. However, a study from the University of Washington shows that there is no evidence that commercial beverages sweetened with either sucrose or high fructose corn syrup have significantly different effects on hunger or how much you eat (American Journal of Clinical Nutrition, July 2007).In another study from Purdue University, subjects were given three different food groups in both liquid and solid forms (International Journal of Obesity, June 2007). No matter what they ate, the subjects ate far more calories on the days that they took in foods in liquid form. This shows that liquid...

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Spot Reduction Exercises Don't Work

Many people believe that if they do enough sit-ups they will get rid of belly fat, but your body does not work that way. Exercising a specific muscle does not get rid of more fat over that muscle in comparison to the rest of your body. If it did, tennis players would have less fat in their tennis arms, and this does not happen. Strength training strengthens weak muscles, but it cannot remove fat specifically over the strengthened muscle.A recent study from the University of Connecticut showed that men who exercised one arm against heavy resistance for 12 weeks appeared to lose more fat in their exercised arm than their inactive one when fat was measured by a caliper that calculated skin thickness (Medicine & Science in Sports & Exercise,...

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Selenium May Increase Diabetes Risk

If you take selenium pills, you may be increasing your chances of developing diabetes, according to a report from the Nutritional Prevention of Cancer (NPC) trial (Annals of Internal Medicine, August 2007). This study is the largest and longest available experimental study of selenium supplements and was done by randomly selecting people for either placebos or selenium and then checking to see who develops diabetes.In 1973, researchers showed that selenium protects against oxidative damage, chemical reactions that damage cells and shorten life. However, there is a narrow margin between getting enough selenium to keep you healthy and taking too much. High levels of selenium bind to and damage many essential body proteins. In the United States,...

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Low Carb Diet Does Not Increase Endurance or Speed

Some athletes and exercisers believe that a low carbohydrate diet will increase their endurance and speed, but there is no evidence that it will. Runners get fuel for their muscles from fat and sugar in muscles, fat and sugar in the bloodstream and, to a lesser degree, from protein. The key to increasing endurance for racing is to store as much sugar in muscles before you race and keep it there as long as possible. Muscle sugar gives you the most energy for the least amount of oxygen.Restricting carbohydrates does not stimulate muscles to store more sugar (Sports Medicine, April-May 2007). A low carbohydrate diet may impair performance if carried out for extended periods because a runner cannot train on a low- carbohydrate diet. If there are...

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Athletes, exercisers and spectators: heed lightning warnings

People who are killed by lightning are often spectators or participants in sporting events. In the United States each year, lightning kills more than 70 people and injures more than 300 people, often permanently. Lightning strikes without warning, so sponsors of outdoor athletic events should have loudspeakers, sirens or horns to alert people to approaching electrical storms.Water, metal and high objects attract lightning. When an electrical storm starts, try to enter a building or your automobile as quickly as possible. Get in your car, not near it. Standing near a car increases your risk of being struck by lightening because you are standing near metal. To avoid being near metal, get off your bike and away from it when you seek shelter. If...

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Napping Makes You Smarter

Two studies from Harvard show that napping make you smarter. I learned this for the first time when I was in the 7th grade. I would be in school from 8 AM to 3PM, go to work in the afternoon, and then come home at 6PM, eat supper and try to study and learn nothing. I would spend more time lying in bed thinking about studying than actually studying. So, in the seventh grade at age 12, I started a lifetime habit of sleeping every afternoon, even if I think that I don't need to sleep. I find that after just 30 to 60 minutes of sleep, I can think more clearly and do more work. If I don't sleep, I cannot write or think clearly. Matthew Walker's study supports what I learned almost 60 year ago. He taught people to type a long list of words on a computer....

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Fasting Triglycerides Test for Heart Attack Risk Unreliable

For more than 50 years doctors have used fasting blood triglyceride levels to predict a future heart attack, but now two studies in the Journal of the American Medical Association show that non-fasting blood triglyceride levels are far more dependable (July 18, 2007). When your blood sugar rises too high after eating, your pancreas releases huge amounts of insulin. Insulin converts sugar to triglycerides. Triglycerides are therefore a marker for a high blood sugar levels that damage arteries to cause heart attacks. More than 75 percent of diabetics die of heart disease.Many people have normal blood sugar and triglyceride levels after an overnight fast, but have their blood sugar levels rise too high after eating and therefore have a high rise...

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Muscle Sugar More Important Than Fluid for Endurance

How fast you can move and how long you can exercise intensely depends on the amount of sugar (glycogen) stored in your muscles. The same rule applies in all sports: when muscles run out of their stored sugar supply, they require more oxygen and you have to slow down.Fluid is less important than muscle sugar because dehydration will not cause you to slow down until your blood volume is reduced. As you lose fluid from sweating, interstitial fluid stored around cells is released into the blood to maintain blood volume. When you compete is sports at a very high intensity, your muscles run out for stored sugar long before your blood volume is reduced, and you slow down from lack of muscle sugar before you slow down from reduced blood volume (Sports...

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Low vitamin D prevents insulin response; sunlight may not be enough

A recent study from the University of Wisconsin Osteoporosis Clinical Research Program in Madison, showed that some people have very low levels of vitamin D in spite of getting a lot of sunlight where they live in sun-drenched Hawaii (Journal of Clinical Endocrinology & Metabolism, June 2007). The 93 participants in the study averaged 22.4 hours per week outside without sun screen. In spite of abundant sun exposure, 51 percent had low vitamin D levels. Many people think of vitamin D as the vitamin that helps to prevent rickets, a disease characterized by weak bones that break easily. However, vitamin D does much more than that. It is necessary for your immune system to search out and destroy invading bacteria, viruses and even cancer...

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