Pacing strategies in track and field

Pacing strategies in track and field are the varied strategies which runners use to distribute their energy throughout a race. Optimal strategies exist and have been studied for the different events of track and field. These optimal strategies differ for runners in sprint events, such as the 100 metres, runners in middle-distance events, such as the 800 meters or the mile run, and runners in long-distance events, such as the 5000m or marathon. Additionally, pacing typically differs between different styles of races. For instance, in a time trial, where the goal of a racer is simply to run the fastest time, participants will typically employ the aforementioned optimal pacing strategy. However, in a championship race, where the goal of the racer is to win, the pace is typically slow in the beginning of the race and gradually speeds up for a sprint finish, often meaning the race is run with a negative split. Typically, to run a world record, the runner must employ a near-optimal pacing strategy.

Track and field racers have a variety of options in the ways they can choose to pace their races.

Even-splitting is a strategy in which the racer attempts to hit the same split in every lap of the race. The racer tries to run an "even" pace during the entire race. In long-distance events, this can often be an optimal strategy.

Positive-splitting is a racing strategy that involves completing the first half of a race faster than the second half. Typically, the runner goes out at a pace faster than he or she can maintain for the entire race, leading to a slower end of the race. Positive-splitting can be employed as a tactic, or can simply be a byproduct of an overambitious early pace.

Negative-splitting is a racing strategy that involves completing the second half of a race faster than the first half. The racer runs slow in the beginning, and gradually runs faster as the race progresses. This is typically seen as a conservative racing strategy, but in distance events, many world records have been run with a slight negative split.

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