When I run, for exercise, I find myself needing to put my mind into focus on something *other* than the running itself. I don’t know if this is common among people – I’m sure some people can just let their minds wander and not really focus on anything, and others can focus specifically on the running (like monitoring themselves for performance and stamina).
Over the years, I have received some advice on what to think about while running. One of my coaches bombarded me with math (I think it was first-year calculus) while we ran on the beach training for cross-country, another told me to focus on imagining that I am holding a potato chip in each hand (making a game of it). I also blast music at full volume when I have my iPod on a run – when there’s a song to sing along to, I have about a 50/50 chance to focus on that rather than get worked up about the workout.
But recently, I have found that considering game design problems is a great way to make the time in the workout fly by. This is probably my obsessive nerdy brain at work, spending all of its attention on the cerebral problems of games (e.g. like staying up all night playing Starcraft) and ignoring physical concerns (e.g. like staying up all night).