system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does exercise help anxiety/depression?
gpt
There are a few reasons! On a purely physical level, exercise increases blood flow to the brain, which influences the hypothalamus, adrenal glands, and pituitary gland. These glands produce hormones, and increased blood flow changes how we react to stress. There are also several psychological factors. First of all, it can simply serve as a distraction. It also increases are sense of self-efficacy, which is the degree to which we believe we can do something. In other words, people who can motivate themselves to exercise are more likely feel like they have control over other aspects of their lives as well.