363 — Association between physical exercise and mental health in 1·2 million individuals in the USA between 2011 and 2015: a cross-sectional study

our new @TheLancetPsych paper was the biggest ever study of exercise and mental health. it caused quite a stir! here's my guided tour of the paper, highlighting some of our excitements and apprehensions along the way [thread] 1/n https://t.co/hvlzstkISR pic.twitter.com/pIzBJiNYQh

— Adam Chekroud (@itschekkers) August 11, 2018

Another super awesome Twitter thread intro to a paper — thanks, @itschekkers!

Exercise is good for you, which probably doesn’t surprise you. But while the benefits of exercise are well-quantified in relation to the prognosis of diabetes, cardiovascular health, and other diseases of “the body,” there’s less literature available on the impact that exercise has on mental health across large population sizes.

This research surveyed the mental health of over 1.2 million (!!!) Americans and compared this with their exercise patterns. After controlling for socioeconomics and demographics, the researchers found that the subjects that exercised were in substantially better mental health than their non-exercising peers: Non-exercisers reported more than 40% worse mental health.

But the amount of exercise was important, too: Exercising for 45-minute sessions made for a lower mental health burden than exercising for more than an hour or less than half an hour; exercising 3, 4, or 5 days out of the week made for better mental health reporting as well.

Team sports, cycling, and other cardiovascular exercise (like jogging) resulted in much better mental health than other activities, though even basic body movement (such as doing chores around the house) was better than not exercising at all.

This is really exciting work because it pays such close attention to the common confounding factors in these sorts of studies. In particular, it was very interesting to see the dramatic effect that exercise had on mental health when compared across high- and low-income individuals: Surprisingly, a large amount of socioeconomic mental health disparity can be explained by amount of physical exercise. Of course, how to enable everyone to have the luxury of setting aside time to devote to personal physical fitness is an entirely different story.