I need to swim 3 times a week and bike to work every day to not bite someone's head off or become depressed. Exercise does all kind of magic things to your bod

I need to swim 3 times a week and bike to work every day to not bite someone's head off or become depressed. Exercise does all kind of magic things to your body. I learned just yesterday that exercise stimulates growth of new mitochondria, which is pretty darn spectacular.