This advice only applies to non-elites.
The tip is: Catch the flu and Lose Weight!
Last fall, I got terribly sick for 7 days and couldn't hardly eat. I lost 12 pounds, from 150 to 138! When I returned to running on day 8, you'd think I would have felt bad from being sick. Instead, I felt AWESOME. My 5k immediately dropped from over 16 minutes to 15:40. I swear I could feel the difference - lighter, easier to run, and faster. Muscle I had put on boxing the previous summer had been shed, and it helped.
So go on. Catch the flu from a coworker, your kids, wherever you can catch it.