I swim laps at the Y. The meditative state my mind enters about 10 laps into a 32-lap mile is amazing. The subconscious bubbles up, as a sibling commenter pointed out, and begins actively problem solving at the surface when your conscious mind subsides. Sibling commenter experienced this while running for thirty minutes.

I have a very peaceful home. It's quiet, safe, a little remote, about an hour or two northwest of Austin in the Hill Country. I have a library in my house where I do most of my work, and sometimes I get on my motorcycle and ride for a bit into the middle of nowhere, which becomes meditative, much like swimming, allowing my mind to work through problems on its own in a very beautiful environment.

I can work (whether it's actual coding or sitting quietly in thought) for 12-14 hours a day, max. Then I must stop and get 7-8 hours of sleep. That balance of good sleep and hard work is key to maximizing productivity and the ability to solve problems during available work hours.

A healthy diet free from high-glycemic foods and foods with a high inflammation index is also very important.