Educational Nugget: Association Physical Activity and Risk of Depression

Submitted by Jessica Foster, Therapy Resource, Bandera, Arizona
What are they saying? (**Definition of PA – Physical Activity)
The Message
The connection between physical activity and a lower risk of depression is well-known, but less is understood about the extent to which higher amounts of PA result in lower risks for depression. Researchers who analyzed the results of 15 studies involving more than 190,000 participants believe they’ve come closer to an answer: Yes, there is a dose-response relationship, they write, but it’s most significant (and predictable) at the lower end of the PA spectrum. Overall, they assert, if less-active adults in the studies had met current PA recommendations, one in nine cases of depression could’ve been prevented.

Why It Matters
Authors believe that establishing the dose-response relationship between PA and depression could be an important tool for health care providers and others in sharing the benefits of even modest amounts of PA, “especially to inactive individuals who may perceive the current recommended target as unrealistic,” they write.

More from the Study
Pinpointing the reasons for PA’s effects on depression were outside the scope of the study, but authors speculate that they could include neuro-endocrine and inflammatory responses, improved physical self-perceptions and more social interactions, and the effects of greater time spent in green spaces. The interplay of these factors needs more study, they add, particularly when considering how individuals with less access to green spaces and greater exposure to noise pollution may experience reduced mental health benefits.

Keep in Mind …
The study is not without its limitations, according to authors. Among them: PA levels were self-reported, data was limited at higher levels of PA, and data was lacking for analysis of demographic subgroups, including those from lower- and middle-income countries.