He takes Adderall my dude. I'm a developer and I use absolutely no cognitive enhancers. If I took Adderall I would be able to code for 20 hours straight. I took a small dose back in college and that stuff is insanely good for long hours at anything.

Also, I'm speculating here, but I think he is on Testosterone Replacement Therapy, which also has insane energy, mood and cognitive enhancements.

Lastly he takes a ton of stimulants.

I don't for a moment think he's working purely off "natural" energy.