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Swedish researchers believe they have found the answer to why exercise works so effectively against depression: When muscles are used, the blood is cleansed of a substance that is harmful to the brain.

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You may have experienced that physical exercise is helpful when you are down? There is also some research that shows that exercise is an effective ingredient in the treatment of depression. But do you know why exercise is so effective?

Well, there may be several reasons for this. Perhaps the most obvious reason is that the body enters a completely different mode than when one is immersed in negative thoughts. Exercising and being active makes your heart pump, you sweat, and you get something else to focus on than just being dark and sad. An additional proof is that you know that it is a "good thing" to exercise; you get in better shape. 

In this post, however, we will focus on one other reason why exercise works against depression. Swedish researchers believe that they have found the answer:

- When the muscles are used, the blood is cleansed of a substance that is harmful to the brain.

This writes HMS Magazine based on a press release from the telegram agency TT.


Cleanses the blood of harmful "stress substances"

The starting point for the study is that, from a purely neurobiological point of view, much is unclear in relation to what characterizes a depression. The researchers in the study in question have tried to investigate in more detail what characterizes a depression physiologically. writes about the same case the following:

- The researchers have performed studies on mice. The study, published in the journal Cell, shows in short that when muscles are active, the blood is cleansed of a substance that is formed by stress - and which is harmful to the brain. They found that trained muscles produce an enzyme that cleanses the body of harmful substances. The muscle function in this context is therefore reminiscent of the function of the kidneys or liver.


Mice with "trained muscles" did not become depressed

The study of the Swedish researchers can be summarized as follows:

- The substance PGC-1A1 is formed when the muscles adapt to physical exercise. The Swedish researchers added this drug to some mice, and not to others, and then they let the whole bunch of mice go through a five-week period with a lot of stress.

- The results showed that the mice that had been given this drug - and thus could be considered mice with "trained muscles" - did not develop depression after being exposed to stress for five weeks.

- On the other hand, the mice that had not been given this drug developed depressive behavior after the five weeks of stress.

In other words, the substance PGC-1A1, which is formed in trained muscles, was shown to be protective against depression.


Physical activity can increase resistance to depression

One of the researchers elaborates on the findings of

- We have described a new mechanism that is found in the muscles, and which affects depression. It is possible that new drugs aimed at this mechanism can be developed. What is clear now is that increased physical activity can increase resistance to depression, says Mia Lindskog to 

There can be many good reasons to be physically active and to use this against depression and heavy thoughts. Knowing that exercise can also have a physiological benefit is another good reason. Then perhaps the big challenge lies in finding a form of exercise that you like - and getting started.

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