A regimen I prescribe a good bit is a 30 second sprint with a minute rest, and in the coming weeks decrease the amount of rest. This is a good place to start since the workout would be challenging but not totally wipe out the CNS, nor cause you to fall down a flight of steps. Take it easy to start and then step it up as it becomes less difficult, just like you would with any weight program you progress by manipulating different variables (rest period, level of difficulty, and total time).