The body is divided into two components, the fat-free body mass and the fat mass. The fat free mass is composed partly of muscle tissue, which does the work. Body composition refers to the relative percentage of muscle, fat, bone, and other tissue of which the body is composed. The success of an athlete depends a lot on the body type. Body size, build, and body composition can impair or help performance.
Body fat contributes no strength advantage and limits endurance, speed, and movement through space.
Olympic cross country skiers are extremely lean compared to average males and females. Training correctly can increase muscle mass, and good nutrition and correct exercise can change body composition. Olympic cross-country skiers need to be muscular for energy demands and lean for good performance. Essential and nonessential fat Essential fat is necessary for temperature regulation, shock absorption, and regulation of essential body nutrients. Nonessential fat is the result of taking in more calories than you expend.