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Running is not a cure-all, but exercise does impact mental health to some degree. Research has shown that physical activity can reduce symptoms of depression, but at what dose hasn’t been quantified—until now.
In a meta-analysis published in April in JAMA Psychology, researchers found that even just performing half the recommended volume of exercise lowered the risk of depression by 18 percent, in comparison to those who didn’t exercise at all. And adults who did exercise the recommended amount (2.5 hours of brisk walking per week) had a 25 percent lower risk.
The robust analysis only included studies that had more than 3,000 participants and a follow-up period of 3 years or more. It included nearly 20,000 participants in total with a physician-diagnosis of depression or diagnostic interview that indicated as such. And 64 percent of the participants were women.
Past publications have shown that people who participate in a large amount of physical activity have lower risks of depression compared to sedentary peers, but this research in particular makes interventions like exercise much more approachable.
According to the World Health Organization (WHO) 280 million people—about 5 percent of all adults—are affected by depression worldwide. But despite how common it is, there is still stigma around the illness that prevents people from seeking treatment (along with other barriers like the cost of care or access to trained healthcare providers).
“Our findings therefore have important implications for health practitioners making lifestyle recommendations, especially to inactive individuals who may perceive the current recommended target unrealistic,” the study authors write. Even a short walk could potentially offer some relief to someone who is struggling.
Why does exercise have the ability to impact our mental health? The answer isn’t completely known, but there are several possible explanations.
For one, exercise actually changes our brain. None of us are strangers to the short-term boost that a run can have on a stressful day (likely through a release of serotonin), but research shows that exercise can help to alleviate long-term depression as well.
That could be because exercise increases the expression of brain derived neurotrophic factor (BDNF), a protein that supports the growth of neurons.
Exercise can also improve sleep, a known way to regulate mood; improve self-esteem; and open up doors to positive social interactions through groups and clubs. Take that exercise outdoors in the presence of natural green spaces and the benefits multiply.
Activating your body also activates your mind; our emotions and behaviors have a reciprocal relationship. We may behave a certain way because we feel sad or angry, for example. But behaviors and actions also have the ability to alter the way we feel. Waiting to feel motivated to go for a run might simply not come. But if you go do it anyway, you might find the motivation coming along afterward. And with it, feelings of accomplishment and improvement that can boost your mood.
But forcing yourself to do something you really don’t want to do is easier said than done. One study published in 2017 in the journal General Hospital Psychiatry found that the majority of the participants knew there was a link between physical activity and their mental health and had a desire to be more active. But mood limiting their ability to do so was listed as a significant barrier.
One way to start is to choose something you truly enjoy doing: That could be anything from running a couple laps around your local park, walking to go get lunch or a coffee, or enrolling in a fitness class you know you’ve enjoyed in the past.
Trying to anticipate your barriers to physical activity and working to get ahead of them can also help. That might mean going to sleep earlier in order to have the energy for physical activity the next day, starting a run from your house to avoid traffic while driving to another starting point, or scheduling time on your calendar for a walk so meetings or other obligations don’t fill up your entire day.
Consulting with a licensed therapist can also help you to discover tips that will motivate you, as well as work through other proven treatment options for depression.