I am trying to get a head-start on being physically fit with a short term goal of the AIM program and long-term goal of Swab Summer. That said, I am not a member of any gym, and I was wondering if joining one is reccommended, or would home work-outs suffice? Also, I've heard a lot of reccommendations to run A LOT... but what else? Obviously push-ups and calisthenics. Any other things that I could use?