Authors from the Institute of Medicine previously offered a report on the health benefits of exercise which were firmly grounded on evidence-based clinical science, but, as I pointed out at the time, ignored the realities of both modern lifestyles and human nature. This earlier report recommended at least 60 minutes of vigorous activity each day for virtually everyone, and more than that if possible. Predictably, that report was widely ignored.
The DHHS decided to take a much more realistic approach, and that approach is reflected in their new guidelines. This report recognizes that, while it is true that the more exercise you do the greater the health benefits, it is also true that the majority of health benefits can be realized with 150 minutes of moderate-intensity exercise each week, a level of physical activity that can be achieved by most of us.
In summary, the new guidelines recommend:
- For children and adolescents, at least 60 minutes of moderately intense exercise daily.
- For healthy adults, 150 minutes of moderate-intensity exercise per week (roughly 20 minutes a day, or 30 minutes 5 days per week).
- For older adults, as much exercise as their physical condition allows, aiming, if possible for 150 minutes per week.
- In addition to aerobic exercise, the total exercise program for all groups should include muscle-strengthening activities roughly twice per week.
Finally, realizing that even this scaled-down exercise program will be too much for many Americans, the new guidelines take pains to point out that some exercise is far better than none at all. That is, the health benefits begin to accrue as soon as you get up and move around. So even if you are unable to meet the recommended activity goals, you should try hard to become as active as possible.
Here's more on the importance of exercise in preventing heart disease.
Source:
2008 Physical Activity Guidelines for Americans. US Department of Health and Human Services. http://www.health.gov/paguidelines/guidelines/default.aspx.
