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...

Read more »

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...

Read more »

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...

Read more »

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...

Read more »

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...

Read more »

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...

Read more »

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,...

Read more »

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,...

Read more »

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...

Read more »

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...

Read more »

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....

Read more »

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...

Read more »

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...

Read more »

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...

Read more »