You might ask this question but the answer is simple, the better you take care of your body the better it takes care of you. Increased energy levels better sleep and increased motivation are all a big part to why its so beneficial to your growth and progress.

What do you do when your not working? Watch tv? Most of America has this for their answer and this is the time you can spend gaining a little muscle and burning calories and still do what it is you do for entertainment. For example you turn on Netflix and pick a show, the show runs for 26 minutes. While this show runs you can do sit ups burpees and if you gran some small weights from the store a few curls and stretches. A great tool is also stretch bands and jump ropes, they are cheap and don't take up a lot of space in your living or bedroom.