I try to explain pacing to my athletes right before every Endurance class when we're deciding on levels. It can be quite difficult to grasp especially when starting out. What I do know is that it takes experience and it takes "feel" from the athlete. I'll continue to express to my athletes that if their going outside the 3 - 5 second window they may as well shut it down. Either the technique is failing or their pacing was screwed up from the first repeat. Shutting down a workout doesn't make you a bad person. It actually means you're running smarter not harder. Learning experiences are key so that you don't repeat the same mistake the next time or worst case on race day. If we draw this back to life isn't it fair to say that people burn themselves out working too much? How about the flip side, those people who never seem to have any sort of drive in life and muddle their way through?
Perfecting pacing is done by...
1 - Practice ... How many times have you done 400m repeats? How about with people or by yourself or in a race? There's always a difference in the environment whether its the weather or running with different people. When you can practice in all dimensions and constantly vary where and how you do things you can make adjustments. Depending on the athlete the next step would be to dial down the rest periods.
2 - Caring... Do you care that you completed 21 Thrusters and 21 Pullups in the first minute and half of Fran, but ended up with a total time of 8 flat? CrossFit, Life, Running - you name it they're activities that require pacing. To perfect it, you have to not only care, but practice. Recognize why your combusting or holding back. Make a change.
3 - Listening... How's your posture feeling? What about your cadence? Are you breathing heavy? Listen to the signs and symptoms of fatigue or mis-pacing just like you would when you get sick. When your training you're the only person out there whose getting the "real time" feedback. Pay attention as much as you do when that first cough or sniffle comes on. Mis-pacing is just like getting sick.
Isn't it cool that if you're doing these three things within your life you're probably a pretty awesome person too? Pace your workouts as you would anyone you come in contact with on the street. Practice, care and listen. It's that simple...
Great video from B Mack - this one's a classic on pacing!