When you exercise, your body uses energy to keep going. Aerobic exercise involves continuous and rhythmic physical motion, such as walking and bicycling. It improves your stamina by training your body to become more efficient and use less energy for the same amount of work. As your conditioning level improves, your heart rate and breathing rate return to resting levels much sooner from strenuous activity.
Exercising with weights and other forms of resistance training develops your muscles, bones and ligaments for increased strength and endurance. Your posture can be improved, and your muscles become more firm and toned. You not only feel better, but you look better, too!