Running can have extremely positive effects on a number of mental illnesses, including anxiety and depression. Individuals who are clinically diagnosed with anxiety and/or depression typically have imbalanced serotonin levels in their brains. Serotonin is a chemical that controls mood. Depression can be a side effect of lowered serotonin levels. Running also impacts other chemicals and neurotransmitters in the brain that regulate mood, including endorphins and dopamine. You've probably heard of a "runners high" - when runners experience an increase in mood and because of a run.
Aside from brain chemistry, running really helps promote better sleep, which can be difficult to come by if you are worried, sad, or anxious. Getting adequate and enough sleep is crucial to helping increase mood and decrease depression and symptoms associated with depression. Running also requires a level of dedication and commitment. Sometimes, those who are depressed need something to not only pour their energy into, but something that will help them establish a balanced routine each day. Studies show that having a steady schedule promotes increased mood. Suggest to your friend to stick to a morning/evening running regimen a few times a week. Not only does this create a definite schedule, but he/she could actually really enjoy running and it could become something they look forward to each day!
Finally, being a runner means you likely have to start paying attention to other ways you are impacting your body - i.e., nutrition and other behaviors. Having a clean diet will not only help you be a better runner, but healthy foods often have a positive impact on the brain and with helping anxiety and depression. Running can also give individuals a heightened sense of self-confidence and self-esteem, which may be critical in lifting your friend out of his depressive state. Running will bring him pride and a sense of self-accomplishment, which may be exactly what he/she needs!
For additional information on how running can benefit your mental health, check out another one of our articles found here.