Exercise is, of course, a natural antidepressant. It leads to the release of endorphins, those chemicals in the brain that help us relax and feel happy. Exercise also simply helps people feel good about themselves because they know they’re acting effectively and doing something that’s good for them. Some studies suggest that exercise is as effective as antidepressant medications at reducing symptoms of depression among adults diagnosed with major depression. Both the biological effects and the psychological effects (increasing self-efficacy and self-esteem and reducing negative thinking) of exercise are thought to be responsible for its positive influence on mood.
In addition, there is abundant evidence that exercise has positive effects on blood pressure and cardiovascular disorders, improves learning and memory, delays age-related cognitive decline, reduces risk for dementia, and improves medical conditions such as diabetes, osteoporosis, and Alzheimer’s disease.
While there are guidelines about how much exercise people should get, anything more than what you’re currently doing is a great start. This perspective helps take the pressure off and makes it more likely that you’ll actually increase your exercise, whereas telling yourself you need to exercise for twenty minutes three times a week could overwhelm you and result in not exercising at all. Of course, if you are working to reform an eating disorder, you may need do the opposite and reduce compulsive or excessive exercise.
Source: DBT Made Simple, by Sheri Van Dijk