How Much Should You Exercise?

Physical Activity Recommendations Really Do Matter

Every time you turn around, it seems like some organization is coming out with a new recommendation about how much exercise you need: 1 hour, 3 times a week; 30 minutes a day; so much aerobic, strength, flexibility –- on and on. These recommendations are based on a combination of science, common sense and “best guess.” What happens when you look at a large group of people over a long time and see how the people who followed the guidelines did in terms of longevity and life expectancy?

In a giant survey of 252,925 men and women aged 50 to 71 years, researchers did just that. They examined reported physical activity levels (compared those to current recommendations) and looked at health outcomes. Over the course of the study, 7,900 participants died. Researchers compared those that died to the rest to determine the impact of exercise. Here is what they found:

• People who exercised moderately at least 30 minutes most days of the week were 27% less likely to die over the course of the study.
• People who exercised vigorously at least 20 minutes, three times a week were 32% less likely to die.
• This benefit existed even in sub-groups like smokers, the overweight, the obese, and people who watched more than 2 hours a day of television.
• People who engaged in less than the two levels of recommended activity also showed a reduction in mortality compared to those that did no exercise.

Exercise is Good For You

Bottom line, exercise is good and will help you live longer. The current recommendations seem accurate. You should try to either exercise moderately for 30 minutes most days (that means at least 5 out of 7) or vigorously for 20 minutes at least three times a week.

For help on exercise, read How To Make Exercise Fun

_Source:

Michael F. Leitzmann, MD, DrPH; Yikyung Park, ScD; Aaron Blair, PhD; Rachel Ballard-Barbash, MD; Traci Mouw, MPH; Albert R. Hollenbeck, PhD; Arthur Schatzkin, MD, DrPH. Physical Activity Recommendations and Decreased Risk of Mortality. Arch Intern Med. 2007;167(22):2453-2460.