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 than women, and have larger muscles and bones, because of their higher testosterone levels. Testosterone helps people to recover faster from hard workouts, so they can do more work and become better athletes. Women exposed to higher levels of testosterone in utero have higher ratios of their fourth to second fingers and often are better athletes.

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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 the "stretch reflex" in the spinal cord sends a message along nerves from the spine to cause the muscle to contract. During fatigue, the muscle retains its contraction to form a cramp. A study from South Africa showed that the most likely cause is muscle fatigue or tearing of the muscle itself. If this is true, muscle cramps during endurance events can be prevented by slowing down when you feel excessive soreness in one muscle group or straining in a muscle. Of course, competitive athletes will not do this, and they pay for it with muscle cramps.

For many years I have recommended eating salted peanuts or other salty foods during heavy exercise, but other doctors believe that extra salt will raise blood pressure. If this is a concern for you, get a wrist cuff monitor and check your blood pressure every day. You are likely to find that your blood pressure goes down, not up, with regular exercise even when you add salt. Journal reference; salt and blood pressure

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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 female hormones usually lower it. This study shows that foods that cause a high rise in blood sugar may increase male hormones, oil production and acne.
Journal reference; explanation of low-glycemic-index diet

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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 liver cells' ability to manufacture triglycerides. At the same time, they can block the LDL receptors on liver cells from removing LDL from the bloodstream. Once again, I recommend getting the nutrients your body needs from food rather than from supplements. Diet to lower cholesterol; how to raise the good HDL cholesterol

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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 stresses the lower leg muscles most, cycling stresses the upper leg muscles most and swimming stresses the arms and shoulders most. Triathletes usually set up a workout schedule that includes two sports on one day and one on the next. Of the three sports, running causes the most muscle damage. Muscles are protected by the water in swimming and by the rotary pedal motion in cycling. However, the force of the footstrike in running tears up muscles. So a knowledgeable triathlete runs on one day and cycles and swims on the next. This way each stressed muscle group has a 48-hour recovery before the next workout. You can apply these same rules for alternating any two or three different activities. Principles of training

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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 forms of food are interpreted in the brain as less filling, and therefore people take in more calories when their beverages contain calories. Interestingly, the increase in calories associated with liquid forms of foods was nearly the same in obese and skinny people.

A single 12-ounce can of soda contains 13 teaspoons of high fructose corn syrup and the average American consumes almost 60 pounds of it, according to the U.S. Department of Agriculture. The leading theory now is that any sugar in liquid form does not make you feel full the way solid food does. Therefore if weight is a problem for you, you should not take in calories in liquid form. Drink water or other zero-calorie beverages instead. More

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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, July 2007). However, when the same authors used an MRI machine to measure fat underneath the skin, there was no difference between the exercised and non- exercised arms.

When you take in more calories than your body burns, you store the extra calories as fat. More than half of the fat in your body is stored underneath your skin and over your muscles. Your stomach will look better when your belly muscles are strong, but sit-ups or crunches will not remove extra fat from your belly. The only way to lose fat from a specific part of your body is to lose weight overall. More on belly fat

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