Various benefits of a good strength-training program is its effect on our overall appearance and body composition. Take, for example, a 170-pound man who has 20 percent body fat–34 pounds of fat weight and 136 pounds of lean body weight (muscle, bones, organs, water, etc.) By beginning an effective strength training program, he replaces five pounds of fat with five pounds of muscle. He still weighs 170 pounds, but he is now 17 percent body fat–with 29 pounds of fat weight and 141 pounds of lean body weight. Although his body weight remains the same, his strength, muscle tone, and metabolism have improved, giving him a firmer, more fit appearance.
…Muscle is Metabolically active – meaning the more muscle your body contains the higher your metabolism is. You burn more calories even at rest when your lean weight or muscle percentages are higher.
…The human body is a very interesting and unique machine. It is unique in that it is the only machine that gets better with use and decreases its capacities without use. It is also unique in that it performs better with variety rather than a single activity.
…Adults who are not on a safe, effective strength-training program will experience an annual half-pound loss of muscle and half-percent reduction in metabolic rate unless they begin some form of strength training. The gradual decrease in muscle and BMR is related to the increase in body fat that most people gain as they get older if they do not strength train. With a decrease in muscle, less energy is used for daily metabolic function, so calories previously necessary to perform the activities of daily living now end up stored as fat.