Physical activity and depresssion

Text: Fredrik Hedlund, first published in the magazine "Medicinsk Vetenskap" no 2, 2016.

What happens in the bodies of experimental animals during physical activity?

“We use animal models in our research and depression is a difficult illness to study in animals. But we can see clearly that physical activity counteracts the harmful effects of stress and that this may be a way to prevent depression. In a review of all human studies that have been conducted in this area that was published in 2014, insufficient support was found to support the statement that physical activity can cure depression.”

What happens during physical activity and how much do you have to exercise to achieve an effect?

“When you exercise, more of a factor called PGC that controls much of the muscles adaptation to exercise is formed. What we have shown is that PGC also increases the breakdown of the substance kynurenine, which is formed in the event of stress and would otherwise enter the brain and is assumed to contribute to the development of depression. The specific form of PGC that we studied is formed during endurance training such as running, cycling and swimming. In humans, it has been shown that 40 minutes moderately hard exercise three times per week is sufficient.”

How can this finding be used?

“One of the difficulties with drugs for depression is getting them into the brain as the blood vessels there are less porous. We have found a mechanism here out in the muscles that can be influenced in order to protect the brain, which creates new possibilities.”