Muscle strength depends on these changes. The greater a muscle's bulk, the stronger it is. Contrary to popular belief, bigger muscles are not inflexible. In fact, building strength will increase flexibility . People with big muscles are not muscle-bound.
Bigger muscles are more efficient.
They produce more energy both anaerobically and aerobically . Fit muscles resist fatigue. Repetitive strenuous exercise causes the brain to release small amounts of chemicals called endorphins , which ease or even mask pain. Exercise breeds hope. Getting the body into shape is living proof that human beings can change for the better.