I was thinking more along the lines of “cooking meat on a spit” (the faster you turn it, the longer it takes to cook), but “sweating” might actually be a better answer… 
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An Olympic Runner’s Career? Start going slow and that career is over real soon, but pick up the pace…
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A bedtime story? From my experience, if you read a bedtime story to kids and talk real slow, they’re out like lights and you get to go on to other things. Read it fast and in an exciting tone, and the kid doesn’t go to sleep.
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Life…if you get in a spaceship and head off at near the speed of light. Once you’re back, everyone else will have aged or died, while you are still young and fresh.