Experts recommend that every week you do one of the following:

1. Two and one half hours of moderate intensity aerobic physical activity throughout the week. (Examples are walking briskly, badminton, cycling, and gardening)    

OR 

2. One hour and 15 minutes of vigorous physical activity. (Examples are race walking, jogging, running, single tennis, and aerobics.)

Aerobic activities should be done in bouts of at least 10 minutes duration. Muscle strengthening activities such as weight training, push-ups, sit-ups, yoga or heavy gardening should also be done at least two days a week. Exercise specialists, also recommend incorporating stretching and other exercises to increase flexibility and avoid injury, as well as exercises to improve balance and reduce risk of falls.

A word of caution:

Exercising is undoubtedly beneficial. But it is not true that the more work out you do or the harder you work the body, the better the results. Excess of physical activity can lead to injuries. Pushing yourself hard will give you good results but do not push your limits too much.

Do read the other articles in this series:

1. Stretching and Balance Exercises

2. Muscle Strengthening Activities

3. Aerobic Activities