One measure of fitness is body composition. Body composition is the makeup of the body in terms of muscle, bone, fat, and water. The amount of lean body mass in proportion to the amount of fat tissue in the body helps determine fitness. The lower the ratio, the higher the body fat and the more unfit we are.
In recent years, “body composition” (usually abbreviated BCA – for Body Composition Analysis – or BIA – for Bioelectrical Impedance Analysis) has been used to determine the correct body weight and degree of obesity. Most sources agree that a man’s body should contain between 11 percent and 15 percent body fat and a woman should be within the range of 18 percent to 22 percent body fat. A man is considered obese if his body fat is over 20 percent, and a woman is considered obese if her body fat is over 30 percent.
The body fat gender difference lies in the structure of the female body and the sex hormones. In females, part of the essential fat is sex-specific fat. In the total female body mass, approximately 4% of body fat is located in the breast tissue. The difference in body fat is also related to hormonal changes during the menstrual cycle and childbearing functions. Women should generally not go below 8% body fat; in men, the lower limit is 3 to 4%. An excessively low body fat in females may lead to amenorrhea, a disruption in the normal menstrual cycle.
The key to the right amount of body fat is to find a level in which you are not at risk for health problems and at which you are comfortable with your appearance.
For most people, a combination of the reduction of calories and exercise will give the desired result of lowered body fat.
Total body exercise will affect the entire body. As you exercise on a regular basis, changes will gradually occur in your body composition. Often in the beginning stages of an exercise program, there is very little weight loss. Instead, the body is redefining its composition and firming up. The muscles get stronger and increase in size, and fat disappears from storage deposits. The body weight remains the same even though there is a fat loss. One way of observing the changes in your body is by recording your body measurements before and during your exercise program. Muscle is firmer and takes up a smaller place than fat. You can often get a better measurement of the changes in your body composition by considering inches rather than the weight scales. If you want to lose weight during the first few weeks, you need to lower your fat and caloric intakes.