Actually, exercise does help to lose weight and reduce fat. As men get older, they have lower amounts of testosterone and and lower muscle mass which results in a lower resting metabolic rate. Muscle tissue burns calories even when you asleep so that calories that might have been converted to fat are consumed by the muscle tissue instead.

Thus, exercise that increases the gluteus maximus (buttock muscle) in your legs, the largest muscle, will increase resting metabolic rate which results in weight loss.