How Much Exercise Do You Need? | The Nutrition Source | Harvard School of Public Health

Exercise Guidelines for Children, Adults, and Older Adults

When it comes to physical activity, some is better than none, and more is better. The 2008 Physical Activity Guidelines for Americans gives general guidelines for children, adults, and older adults. (1) When reviewing the guidelines, keep two things in mind:

• If you don’t currently exercise and aren’t very active during the day, any increase in exercise or physical activity is good for you. Start slow, and gradually build up the length and intensity of your workouts over time.
• You don’t need to log all of your daily activity in one session: You can accumulate physical activity in 10-minute bursts, spread throughout the day.

Here is a summary of the guidelines for children and adolescents, adults, and older adults. More information is available on the Physical Activity Guidelines for Americans website.

Children and Adolescents

Get at least 1 hour or more a day of physical activity in age-appropriate activities. Spend most of that hour in moderate- or vigorous–intensity aerobic activities. Make sure to get vigorous-intensity aerobic activity on at least three days of the week, and include muscle-strengthening and bone strengthening activities on at least three days of the week. (Read more about muscle strengthening activities.)

Healthy Adults

Get a minimum of 2-1/2 hours per week of moderate-intensity aerobic activity, or a minimum of 1-1/4 hours per week of vigorous-intensity aerobic activity, or a combination of the two. That could mean a brisk walk for 30 minutes a day, five days a week; a high-intensity spinning class one day for 45 minutes, plus a half hour jog another day; or some other combination of moderate and vigorous activity. Doubling the amount of activity (5 hours moderate- or 2-1/2 hours vigorous-intensity aerobic activity) provides even more health benefits. Adults should also aim to do muscle-strengthening activities at least two days a week. (Read more about muscle strengthening activities.)

Older Adults

Healthy older adults should follow the guidelines for healthy adults. Older adults who cannot meet the guidelines for healthy adults because of chronic conditions should be as physically active as their abilities and conditions allow. People who have chronic conditions such as arthritis and type 2 diabetes should talk to a healthcare provider about the amount and type of activity that is best. Physical activity can help people manage chronic conditions, as long as the activities they choose match their fitness level and abilities. Even just an hour a week of activity has health benefits. Older adults who are at risk of falling should include activities that promote balance.

References

1. U.S. Dept. of Health and Human Services. 2008 Physical Activity Guidelines for Americans. 2008. Accessed December 2, 2010.