Great article by Scott Dinsmore on "How Richard Branson Started Over 400 Companies: The most powerful productivity (& confidence) hack of all time". As a Master Key System student it'll be hardly news for you, but it's still worth reading, especially the comments at the bottom of the article.
Bottom line: if you want get done more or become better, then WORK OUT! Physical exercise is the key to so many positive changes. It goes hand in hand with all the improvements you perform on your mental, emotional and spiritual side, because without adequate health, your efforts will be thwarted.