Effect of exercise on muscles

Hey Bhavya,
Exercises have its important effects on muscles and bones.
1) Researches have shown that the people who exercises are lean and stronger than non exerciser peoples.
2) Exercises helps build up muscles and increase muscle fiber in size.
3) Exercises makes muscles stronger and thus it helps to reduce stress on weight bearing joint. i.e. Exercises improves condition for acute osteoarthritis of weight bearing joint.
4) Exercises working mainly on strengthening of back muscles can help improve posture and thus can reduce risk of hunchback in the peoples of osteoporosis.
5) Obesity puts alot load on back and weight bearing joint, so exercises help to reduce the body weight as well as makes the muscles surrounding joint more stronger and thus help to support joint.
Thus, are various good effects if we exercise daily or atleast 5/week including both types of exercises i.e. Cardio and weight training exercises in our exercise programme.