Aside from the many miles of training you log in preparation for a half marathon, most runners also spend a good amount of time figuring out race-day logistics. You have to decide what you'll wear, what you'll eat, and how you'll get to the start.
Unfortunately, when it comes to gun time, many runners enter into races without a pacing strategy. This often leads to going out too fast and hitting a wall in the final miles. Indeed, it's often said for every minute you run too fast the first half of the race, you'll run around two minutes slower in the second half.
There are two major reasons runners end up positive splitting, or running the first half of the race faster than the second half. The most obvious is excitement. The crowds are cheering, music is playing, and adrenaline is pumping. When your legs feel fresher than fresh, it can be difficult to hold yourself back from churning out miles far faster than your ideal pace. At some point this happens to everyone.
The other reason is a result of lack of planning. While you were busy putting together your race-day outfit, you forgot to test out your race-day pace. Without an idea of what pace you're capable of, it's easy to end up going out too fast and running out of gas too soon. Simply going by feel will almost always elicit this result. Although your long runs may have given you some idea of the speed you should travel, they aren't the most accurate test.
Steven Miller, owner of Running Your Best coaching service based in Massachusetts, suggests using an online race calculator that can help you begin to sketch out a pacing strategy.
"By entering a recent performance at another distance, these formulas can ballpark what you should be capable of doing at another distance," he says. Most runners will do this by running a shorter race, like a 10K, to see what might be realistic for the half marathon.
Another method to nail down your race-day pace is via a predictor workout several weeks out from the half marathon. These types of workouts, if done correctly, will elicit a ballpark pace that you should be able to maintain if all goes well on race day. To be sure, it will also help you avoid hitting the wall with several miles to go.
"These workouts are great because they help encourage runners to go out more conservatively," Miller says. "I've never had a runner say, 'I wish I would have gone out faster.'"
More: 4 Ways to Train Smart