Perhaps the three most important considerations determining ideal body composition are health, aesthetics, and performance. The average person tends to be most concerned with health and aesthetics, while the athlete is concerned about all three.
Although the ideal healthy fat percentage has not been clearly established, it is generally agreed to be between 16% and 25% for women less than 20% for men，actually the average man and woman fall above the recommended fat percentage in almost all age categories. Tile ideal aesthetic body composition is even more difficult to establish. In our society, the lean, athletic look is prized, while the more corpulent look of the turn of the century is disdained. Unfortunately, the quest for the "lean look" often leads to unhealthy dietary habits. This is especially disturbing among athletes, who usually have very high caloric requirements because of heavy training. Young teenage, female athletes seem to be especially prone to overzealous caloric restriction, which can be dangerous.
Body composition is an extremely important consideration in many sports. In sports with weight categories, such as wrestling, boxing, and weight lifting, serious abuses have taken place in an attempt to lose weight. Weight - loss practices have sometimes even compromised the health of the athletes. Successful athletes in various sports usually possess a characteristic body composition. Variability in body fat depends on the metabolic requirement of the activity and the relative disadvantage of carrying an extra load. For example, successful male distance runners are almost always less than 9% fat. For these athletes, excess fat is a decided disadvantage. The tremendous caloric cost of running long distances makes it difficult for runners to gain much fat.
Football linemen, however, are almost always greater than 15% fat. This may be advantageous because of the added mass and padding provided by the subcutaneous fat and the increase in lean mass that accompanies excess weight (muscle mass accompanies gains in fat to support the extra weight). Unfortunately, many younger athletes gain too much fat in an attempt to attain the high body weights of the professional football player.
