Adults gain substantial health benefits from two and a half hours a week of moderate aerobic physical activity, and children benefit from an hour or more of physical activity a day, according to the new Physical Activity Guidelines for Americans by the U.S. Department of Health and Human Services.

The guidelines are designed so people can easily fit physical activity into their daily plan and incorporate activities they enjoy.

"It's important for all Americans to be active, and the guidelines are a roadmap to include physical activity in their daily routine," HHS Secretary Mike Leavitt said. "The evidence is clear--regular physical activity over months and years produces long-term health benefits and reduces the risk of many diseases. The more physically active you are, the more health benefits you gain."

Regular physical activity reduces the risk in adults of early death; coronary heart disease, stroke, high blood pressure, type 2 diabetes, colon and breast cancer, and depression. It can improve thinking ability in older adults and the ability to engage in activities needed for daily living.

Leavitt says that the Physical Activity Guidelines for Americans are the most comprehensive of their kind. They are based on a review of scientific research about physical activity and health in more than a decade. A 13-member advisory committee appointed in April 2007 by Secretary Leavitt reviewed research and produced an extensive report.  

Key guidelines by group are:

• Children and Adolescents--One hour or more of moderate or vigorous aerobic physical activity a day, including vigorous intensity physical activity at least three days a week. Examples of moderate intensity aerobic activities include hiking, skateboarding, bicycle riding and brisk walking. Vigorous intensity aerobic activities include bicycle riding, jumping rope, running and sports such as soccer, basketball and ice or field hockey. Children and adolescents should incorporate muscle-strengthening activities, such as rope climbing, sit-ups, and tug-of war, three days a week.  Bone-strengthening activities, such as jumping rope, running and skipping, are recommended three days a week.
• Adults--Adults gain substantial health benefits from two and one half hours a week of moderate intensity aerobic physical activity, or one hour and 15 minutes of vigorous physical activity. Walking briskly, water aerobics, ballroom dancing and general gardening are examples of moderate intensity aerobic activities. Vigorous intensity aerobic activities include racewalking, jogging or running, swimming laps, jumping rope and hiking uphill or with a heavy backpack. Aerobic activity should be performed in episodes of at least 10 minutes.  For more extensive health benefits, adults should increase their aerobic physical activity to five hours a week moderate-intensity or two and one half hours a week of vigorous-intensity aerobic physical activity. Adults should incorporate muscle strengthening activities, such as weight training, push-ups, sit-ups and carrying heavy loads or heavy gardening, at least two days a week.
• Older adults--Older adults should follow the guidelines for other adults when it is within their physical capacity. If a chronic condition prohibits their ability to follow those guidelines, they should be as physically active as their abilities and conditions allow. If they are at risk of falling, they should also do exercises that maintain or improve balance.
• Women during pregnancy--Healthy women should get at least two and one half hours of moderate-intensity aerobic activity a week during pregnancy and the time after delivery, preferably spread through the week. Pregnant women who habitually engage in vigorous aerobic activity or who are highly active can continue during pregnancy and the time after delivery, provided they remain healthy and discuss with their healthcare provider how and when activity should be adjusted over time.
• Adults with disabilities--Those who are able should get at least two and one half hours of moderate aerobic activity a week, or one hour and 15 minutes of vigorous aerobic activity a week. They should incorporate muscle-strengthening activities involving all major muscle groups two or more days a week. When they are not able to meet the guidelines, they should engage in regular physical activity according to their abilities and should avoid inactivity.
• People with chronic medical conditions--Adults with chronic conditions get important health benefits from regular physical activity. They should do so with the guidance of a healthcare provider.