Physical- It can, potentially, make you a fit, trim and healthy person. Duh.
Emotional- It can help you redirect harmful sentiments such as anger and depression away from you and into something that will be unaffected by them. Not to mention, it raises your spirits with that awesome exercise “high”!
Mental- It helps you think deeply and refocus your mind. This allows you to sort thru the junk in your mind and the stuff that actually matters.