Cycling Does Not Weaken Bones

A recent article from France may explain why some top bicycle racers have low bone densities, indicating an increased risk for breaking their bones (The Physician and Sportsmedicine, October 2010). Nobody has ever shown that bicycling or any other type of exercise weakens bones. I discussed this in detail in my 9/12/10 eZine.

We may now have an explanation for the weak bones found in some elite bicycle racers: they could have taken glucocorticoids to help them ride faster. These drugs, taken for just a few days, take calcium out of bones to cause low bone density, osteoporosis and bone fractures. Examples of glucocorticoids include Cortisone, Dexamethasone, Hydrocortisone, Prednisolone and Prednisone.

Female athletes who were not competitive bicycle racers were given 50 mg of prednisone per day for one week and then tested to see how long they could continue cycling at 75 percent of their maximal output (VO2max). They were able to last 66.4 minutes after a course of prednisone, compared to only 47.9 minutes after placebo (European Journal of Applied Physiology, November 2009). That's an incredible 30 percent increase in endurance time.

The limiting factor in how fast you can ride a bicycle or run, ski or skate over long distances is the time it takes for oxygen to get into your muscles. Therefore anything that decreases your need for oxygen will help you to move faster over distance. Sugar requires less oxygen than fat or protein to be converted to energy by your muscles. So anything that causes your muscles to burn more sugar, and less fat, makes you faster. Corticosteroids markedly elevate blood sugar levels. For example, a normal blood sugar is below 100. After taking steroids, your blood sugar can rise over 300.

Glucocorticoids, taken in pills or injections, are banned by the World Anti-Doping Agency (WADA) during competition. Athletes get around the rule restricting corticosteroids by claiming that they have *asthma treated with steroid inhalers, *certain skin disorders treated with steroid creams, or *muscle or joint injuries, immune disorders or diseases treated with steroid creams, pills or injections.

People should take glucocorticoids only if they need them to treat a serious, usually life-threatening disease. Not only can glucocorticoids cause permanent osteoporosis, they also can increase risk for diabetes, high blood pressure, heart attacks and fat gain. They are very different from the anabolic steroids that some athletes take to grow larger and stronger muscles.

Full Fat Cells Cause Heart Attacks and Strokes

A diet of fruits, vegetables and nuts lowers the bad LDL cholesterol in two weeks by 33 percent, far more than the same diet with added grains and low fat diary (23 percent), and even more than by the National Cholesterol Therapeutic Step-2 diet recommended by doctors for people with high cholesterol (7 percent). Even more important, the ratios of LDL/HDL cholesterol are reduced by 24 percent, 12 percent, and 5 percent respectively (Epidemiology, March 2006).

This study by David Jenkins and many other studies show that the most effective way to lower high cholesterol and blood pressure, prevent heart attacks and prolong life is to avoid taking in more calories than you burn. Limiting food intake to just fruits, vegetables and nuts makes it very difficult to meet your needs for calories. You have to eat all day long to get enough calories just to maintain your weight. This diet is almost the same as what human ancestors ate four to seven million years ago before they split off in development from apes, who eat almost the same way in the wild today.

Further evidence that extra calories cause heart attacks comes from the fact that reducing your intake of calories by one third and eating nothing but fatty meats and diary products will cause your blood cholesterol level to go down (European Heart Journal Supplements, 1999;1(S):S19-S23). Saturated fats are broken down in your liver to two-carbon acetyl units. If you take in more calories than you need, the acetyl units are used as building blocks to make cholesterol and your blood cholesterol level rises. On the other hand, if you are not taking in extra calories, the acetyl units are burned for energy and do not raise cholesterol.

The fruit-vegetable-nut diet is extremely low in significant amounts of starch because humans did not eat large amounts of grains until the agricultural revolution about 10,000 years ago. By adding whole grains and animal products to the fruit-vegetable- nut diet, humans suddenly increased their caloric intake dramatically. Their bodies were used to trying to get every calorie they could possibly get from the food that they eat. Now they could get all the calories they needed. As long as they were very active physically, they could compensate for the extra calories that they could take in and use. However, as soon as humans stop being physically active, they start to store extra calories as fat and it is the extra fat that causes much of modern day disease.

Adding low-fat dairy products, whole grains and dried beans to a fruit-vegetable-nut diet creates a diet that is low in saturated fat and low in cholesterol. This is the basis of the therapeutic diets recommended by most physicians to help prevent heart attacks today, yet these diets are significantly less effective than the fruit-vegetable-nut diet that forces severe calorie restriction.

The most unhealthful diet is one that allows you to take in more calories than you need *so you store more fat in your muscles, *fat in cells blocks insulin receptors, *your cells stop responding to insulin, *your blood sugar rises, *sugar sticks to cell membranes to damage cells and cause *diabetes, heart attacks, strokes, cancers, and premature death.

If you have high cholesterol, high blood pressure, heart disease or diabetes, try limiting your diet to fruits, vegetables and nuts for just two weeks. It is likely that your cholesterol and blood pressure will drop significantly in that short time, and you will have identified the source of your problem.