The topic: You do have time to exercise, according to a new study in Lancet. Here's why it matters.
Everybody knows exercise is or would be good for them. It helps your heart. It maintains your mind. It relieves stress. But how much is enough? The general recommendation for adults is at least 150 minutes total each week. That's slightly more than 20 minutes a day, which is 20 minutes more than many people claim they have.
A new study in Lancet obliterates that excuse. Conducted in Taiwan, the study followed more than 400,000 people for more than 8 years. Participants kept exercise diaries and self-reported weekly exercise as inactive, low, medium, high, or very high. It turns out that even the low average, which was 15 minutes of exercise a day, reduced mortality, with a 10% decrease in cancer death, 14% decrease in death overall, and an average increase of 3 years of life. Whereas even a low amount of exercise is good, more is better. Each additional 15 minutes of daily exercise -- half an hour total -- produced an additional 1% decrease in cancer death and an additional 4% decreased risk for death overall. Participants who could not find 15 minutes to spare and did not exercise at all had a 17% higher death risk compared with even the low exercise group.
This is an observational study, but its bottom line is that just 15 minutes a day -- 105 minutes a week -- of moderate-intensity physical activity is all it takes to reap major benefits. A little bit of exercise can do a lot of good, and some is always better than none.
- Wen CP, Wai JP, Tsai MK, et al. Minimum amount of physical activity for reduced mortality and extended life expectancy: a prospective cohort study. Lancet. 2011;378:1244-1253. Epub 2011 Aug 16. Abstract
- Office of Disease Prevention & Health Promotion, U.S. Department of Health and Human Services. 2008 Physical Activity Guidelines for Americans Summary Accessed December 13, 2011.