A couple of people in the forum are asking about how to pace a race. While they were asking about how to pace, in their questions, they were actually describing the way to do it. Here are those dialogues (edited for clarity):
Q: I raced today, my 2nd one in the season. … Well today I was going to blow up trying to run at my best pace. I stared out 15 seconds slower for a few miles, then started to build into my race pace. Around 5 miles I noticed I would not meet my projected race time even with running at that pace and slightly faster. So I started to pick it up even more running 30 seconds faster than my goal so I could meet my time. I finished on time felt good too.
So should I run my race slower than the [race pace] and build or run my race at pace and build if I can ?
A (me): You have discovered the best way to pace any endurance race or time trial. I’ve read some studies of world record distance races, and reports are that usually there is a very slight negative split involved.
As to determining how fast to go at any particular point in a race, here are my thoughts: I’ve found the VDOT to be a great tool for training, and I’ve found training to be a great way to ingrain into my brain and body what it feels like to run at various speeds – what effort is involved in running at 5K pace compared to half marathon pace, etc. Also, I’m lucky in that my HR at any effort level is very stable, and I can use that as a check on how I am doing.
I think there are a lot of reasons NOT to use a pace watch to determine how “fast” or “hard” to go during a race. Terrain is variable, so running at 7 min/mile uphill is entirely different than downhill. No matter how you cut it, there will always be a disconnect between what you see on the watch and how fast you are going: the built in GPS elevation “dither” confusing the algorithm, the effect of smoothing, delay in screen display, etc.
So what I do is go by my perceived rate of exertion (RPE), checked by HR. No matter the distance involved, I try to do the first 5-10% at an effort level which seems “easy” for that distance (i.e,, easy will feel slower for a marathon than a 5K). Then, I try to get into the RPE gear that training has taught me reflects the goal pace I have for the race. By the time I hit the 3/4 distance mark of the race, I should be feeling that I am working quite hard, and would be happy to finish at that pace. That’s when mental toughness takes over. I try to turn it up GRADUALLY at that point. If I’ve trained and tapered well, I can finish the race with an increasing effort level. If not, I start to sputter and cough like a car running out of gas. I can’t hold turnover, my breathing gets ragged. When I’m racing well, the last 3-4 minutes should be bordering on a constant battle with myself to quit.
What are the RPE cues I go on? The biggest is rate of breathing – how many steps per breath. Another is cramps in my muscles – if they start to appear, I’ve gone too fast too soon. And a third is HR as I’ve noted – I can use that to tell me if I’m going to fast or too slow if I have any doubts. Oh, and when your vision gets dark with flashing lights and tunnel vision … you may have overdone it.
Q:I have noticed that in training and racing I tend to pace myself with somewhat of a “buffer”. I seem to go at a pace that feels as fast as I can handle but when I know that I am within reach of the finish I can suddenly push that little bit harder. It is difficult to explain because I am pushing hard but my body/subconscious seems to be protecting me from blowing up. The OS has taught me to push harder than ever before but there is still a feeling of leaving a little bit on the table.
Should this be something that I work harder at overcoming or will it come naturally with more racing?
Is it at all beneficial in ironman racing?
If I should work on this, what are some techniques to start pushing to the absolute limit?
A: Learning how to pace a race is of course a significant key to success. The fact you are aware of what your body is letting you do is an important element of being able to pace well.
I think the best way to train for pacing is to open up your awareness during your normal workouts. Learning what your body is capable of at various levels of effort and attempts to hold pace/power is part of what is improving during a training program. Just as your muscles and heart are getting fitter, so is your brain, even the parts of it “you” are not aware of. You’re learning the best way to race is just get out of the way and let your trained body/brain do the work.
While “pushing to the limit” means something different in an Ironman than in a 5K, the concept is the same; its just the time frame and effort level which are different. The model you are describing will work in any race.
Stay on this path; it will lead to success.