The fine line between measuring accurate pace and simulating race day situations. – By Susan Paul
This topic actually comes up quite frequently among runners, and it can turn into quite a heated debate. There isn’t a “right or wrong” answer to this question, but having an idea of your total run time — from start to finish — is a more accurate prediction of your race performance than just your run pace alone. It’s been my experience that stopping your watch every time you take a break gives runners an inflated idea of their performance.
During any race, especially longer distance races like a half marathon, you may very well have a toilet stop or two (you may even have to wait in line to use it!). Or, you may need to tie a shoe, slow down to drink water, take in nutrition and so on.
If you have trained to factor in these pauses, you’ll have a more realistic idea of your race time. Even better, you can gear your training to be prepared for such breaks and even offset them.
If you have a specific race pace or time goal in mind for your race, you can do some speed training to make up for time lost, in whatever way it may come. As you experience these slow downs or brief stops, practice picking up the pace afterward. This can turn a training run into something like a fartlek run as you speed up after a slow down.
Varying run paces is very helpful to training because it appears to help stave off fatigue and reduce the risk of injury. It also better simulates what will probably happen on race day, too.
The good news is that since you are running with a partner, one of you can stop your watch and record on-the-run pace and the other can leave the watch running for total run time. This will provide you with even more valuable training information.
You can see how much stops cost you and how much you may need to speed up to hit your goals. As always, the more you can simulate race day during training, the better your preparation becomes.