Exercise Lengthens Life Regardless of Weight

Just a couple of hours of physical activity each week adds years to average life expectancy. Katherine Harmon reports

Join Our Community of Science Lovers!

A little exercise each week can lead to big gains in life expectancy. And that’s true regardless of your current weight, according to a new review study that included more than 650,000 people. 

The World Health Organization recommends two-and-a-half to five hours of brisk walking per week, or less time spent at a more vigorous activity. People who got the full recommended amount of exercise saw an average 3.4-year gain in life expectancy. People who got half as much exercise still lived an average 1.8 years longer. The findings are in the journal PLoS Medicine. [Steven C. Moore et al., Leisure Time Physical Activity of Moderate to Vigorous Intensity and Mortality: A large pooled cohort analysis]

In fact, exercise was a bigger factor than body weight in many cases. People who were normal weight but were inactive actually lived an average of 3.1 fewer years than obese people who kept up high levels of activity.  


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Finding time to exercise can be tough. Maybe look at it this way. There are almost 9,000 hours in a year. Five hours a week is 260 hours a year—to get an extra 30,000 hours of life. Do the math. While you take a walk.

—Katherine Harmon

[The above text is a transcript of this podcast.]

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe