How fast are you running? Ask yourself mid-run—no peeking at your GPS—and chances are, you'll get it wrong.
Research shows that recreational runners overestimate or underestimate their pace by 32 to 40 seconds per mile. And many assume that unless they're training for a specific time goal, pace doesn't matter anyway.
It does, says Coach Ewen North, of Colorado-based Revolution Running.
"Even if you're just out there to stay physically fit, being cognizant of pace can help you stay out longer and complete your run, so you get more endurance benefits."
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For those gunning for a PR or tackling a new distance, pacing is even more vital, says Carl Foster, Ph.D., an exercise scientist at University of Wisconsin-Lacrosse. Starting too fast can have disastrous physiological effects mid-race, and finishing with too much in the tank can take a toll on ego and finishing time.
"The objective at any distance is to run out of whatever you have to give one step beyond the finish," Foster says. To do that, you have to know exactly how to pace yourself.