Body fat percentage: more important than weight?

People come in many different shapes and sizes, with varying builds and fitness levels, so weight often is deceiving. In the 1990s, more emphasis is being put on the percentage of muscle and fat, and less on total body weight.

Measuring body fat, rather than weight, is the best indicator that a person needs to trim down. Numerous studies have shown that elite athletes - including gymnasts, cross-country skiers, swimmers, and distance runners - have significantly lower percentage of body fat than the rest of the population.

What is the relationship between low body fat and world-class ability? "Excess body fat is |dead weight," explains Steven Heymsfield, associate professor of medicine, Columbia University. "It's harder to perform when you are, in effect, carrying around a sack of potatoes."

According to the American Heart Association, accumulating fat starts earlier in life than once thought - at 25 for the average American. Some body fat, of course, is essential. Fat tissue protects the body against injury, insulates against cold, and supplies fuel to meet energy needs. However, too much fat puts individuals at risk for a host of ailments, including diabetes, gallstones, high blood pressure, and heart disease.

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