A: They make you feel good.
And apparently, according to new research, they may all use the same mechanism (known as the endocannabinoid system) to give you that sense of euphoria. So tell that to non-runners who say things like:
- "Isn't running bad for your knees?"
- "I wouldn't drive 26 miles in a car, much less run it!"
- "Runners are crazy."
(For more info, see this week's NY Times story)