Exercise is great for every age. Not only do you look fitter when you have a regular exercise routine, but you feel better when you exercise, your health is better, you're in a better mood, and you have more energy. Although going to a gym, taking an aerobics class, or exercising with a DVD are a lot of fun, they cost money. If you or your parents want to pay, great! Otherwise, you can put together your own exercise routine for free. If you can convince a friend to exercise with you, it'll be a lot more enjoyable. While the American College of Obstetricians and Gynecologists recommends that teenage girls get an hour of exercise a day, you can divide that time into three 20-minute chunks if you have a hard time setting aside a whole hour.
Most of the time you spend exercising should be aerobic, like jogging, dancing, skating, or other activities that have you moving those muscles and getting that heart pumping. Exercises that strengthen your bones are also important, including playing tennis and jumping rope; and those that strengthen muscles are also key, like rock climbing and weight lifting. No, you don't have to buy a set of barbells; doing exercise to music while lifting canned goods or bottled water counts as weight-bearing exercise also. Warm-up and warm-down can be as simple as walking before and after your jogging exercise. Just remember that if you haven't exercised before, you should start your exercise program slowly and gradually add a few minutes each day. If anything hurts, stop and rest.
If you find you're getting bored with your exercise routine, it's time for a change of pace. Switch activities from time to time; start biking every other day with a friend or go swimming. The advantages to having a friend with you are that you'll feel less embarrassed than if you exercise by yourself, you have someone fun to talk to, and the time goes by a lot faster.