Many entrepreneurs like to project an image of themselves as solely positive-thinking, productive leaders with a special immunity against negativity, but research has shown that founders are over four times as likely to have a history of depression as the general public.

That's nearly a third of entrepreneurs at risk of having a depressive episode. Some have learned how to manage their mental health issues, but others may still need the tools and information to do so.

Now, research out of Harvard University and Massachusetts General Hospital (MGH) finds that blocking out a small amount of time each day for exercise may actually provide a little of that imagined immunity against depression for entrepreneurs, and anyone else. 

Researchers published a study in the journal Depression and Anxiety in early November that found people who exercise several hours or more weekly are less likely to be diagnosed with a new episode of depression. This pattern held true even for those at high genetic risk of depression. 

"Our findings strongly suggest that, when it comes to depression, genes are not destiny and that being physically active has the potential to neutralize the added risk of future episodes in individuals who are genetically vulnerable," said Karmel Choi, the lead author of the study, in a release.

She adds that 35 minutes of additional physical activity a day can be enough to reduce that risk, whether it is a high intensity run or something more mellow like yoga or stretching. The researchers found that overall there was a 17 percent reduction in the odds of a new depressive episode diagnosis for each additional four hours of physical activity per week.

The study was conducted using electronic health data from nearly 8,000 participants in a research database started at MGH. 

It's important to note that this study is observational and uses some self-reported data, which means that as scientific evidence goes, it's not the strongest. It shows a correlation (rather than a causal link) between people's exercise habits and fewer depressive episodes, even among people who carry a genetic risk for depression. 

Regardless, the notion that exercise can be a salve for depression isn't exactly new. This study really serves to bolster what we kind of already knew. And it's important to consider not just for entrepreneurs in their own lives, but also as employers of people dealing with similar risks. 

Surveys have shown that two out of three people see evidence of depression where they work. So in addition to making sure that you're setting aside the time to get moving for the sake of both your mental and physical health, don't forget to encourage your employees or co-workers to do the same. 

We're not meant to look at screens our whole lives. Which reminds me, it's about time I got running.