What is the minimum?

In 2007 the American Heart Association and the American College of Sports Medicine released a joint statement on "Physical Activity and Public Health". The statement doubled the previous standards of moderate-intensity aerobic activity.

"To promote and maintain health, all healthy adults aged 18 to 65 years need moderate-intensity aerobic (endurance) physical activity for a minimum of 30 minutes on five days each week or vigorous-intensity aerobic physical activity for a minimum of 20 minutes of three days each week. Combinations of moderate and vigorous intensity activity can be performed to meet this recommendation. Moderate intensity aerobic activity is generally equivalent to a brisk walk and noticeably accelerates the heart rate. Vigorous intensity aerobic activity is exemplified by jogging, and causes rapid breathing and a substantial increase in heart rate."

It is important to understand that this is considered the "minimum" .

"...persons who wish to further improve their personal fitness, reduce their risk for chronic diseases and disabilities or prevent unhealthy weight gain may benefit by exceeding the minimum recommended amounts of physical activity."