"Aerobic" means "with oxygen." For a sport or activity to be aerobic, you need two things:
Because muscles need oxygen for aerobic exercise, your heart and lungs work harder to supply the oxygen. Working your heart and lungs like this makes your heart stronger and your lungs work better.
Aerobic activities include:
A good aerobic workout lasts 20 to 60 minutes. As soon as you start, the amount of energy you use increases. (You may use between three and 15 times the amount of energy you use when sitting.) This jump in activity is very good for you. How often do you need to workout? Spend at least three hours each week on aerobic exercise to strengthen your heart.
Aerobic exercise also:
Aerobic exercise is also one of the best ways to lower your blood pressure and reduce body fat. And daily exercise helps relieve stress and can prevent or reduce depression.
See Setting Up an Aerobic Program for help on getting started today.