Negative Splits
A “negative split” in running simply means the second half of your run, race, or interval is faster than the first half.
Anyone can run fast and then slow down, but not every runner can start at a strong pace and then speed up. A runner who can execute negative splits on demand demonstrates good pacing skills. (The exception is a runner who starts way way too slow and then has a huge negative split. That really isn’t great pacing.)
Here are some examples:
Examples of Negative splits in a 4 MILE TRAINING RUN:
8:47/8:40/8:05/8:00 — each mile gets faster
8:00/8:05/8:05/7:55 —the second half of the run is faster than the first half
8:05/8:06/8:02/8:01 — This a very evenly paced run although there is a tiny negative split! The second half of the run is 7 seconds faster than the first half. These 7 seconds are not very significant.
Examples of Positive splits in a 4 MILE TRAINING RUN:
8:00/8:05/8:40/8:47 — each mile gets slower
8:00/7:55/7:50/8:20 — last mile is the slowest, and the second half of the run is slower than the first half
8:00/7:55/8:36/7:58 — last mile is strong but the second half of the run is still slower than the first half
8:07/8:02/8:05/8:06 — This is very evenly paced although there is a tiny positive split. The second half is only 2 seconds slower than the first half. 2 seconds over the course of 2 miles is negligible.
Examples of Splits in a SINGLE 400m INTERVAL (total time of 80 sec)
Even splits: 40 seconds at 200m, and 40 seconds to finish.
Positive splits: 38 seconds for the first 200m, 42 seconds for the second.
Negative splits: 41 seconds for the first 200m, 39 seconds for the second 200m
To develop good pacing skills, intervals in a workout should be run relatively evenly split. Ideally we try to avoid positive splits.
That being said, if the goal is 80 for the 400m, each of these intervals is a success - even the positive split.
If a runner notices they have started too fast and slows down intentionally, that is good. It demonstrates good control of pace while running. However, if the positive split is a result of starting too fast and fading (not purposefully, but due to fatigue) then it is not ideal. The runner should start slower in the next interval to avoid another positive split. The goal is always to finish strong and in control.
Consider an INTERVAL WORKOUT: 6x 400m (or quarter mile):
The term “negative splits” isn’t usually associated with interval workouts as a whole, the term is used for continuous running, like a 4 mile run or a 400m interval which don’t have recovery breaks. But the concept of negative splits applies to workouts too. We want to finish faster and stronger than we started. We want to avoid slowing down in the second half of the workout.
Not Ideal:
1:20/ 1:20/ 1:22/ 1:23/ 1:25/ 1:27 — trending slower as the workout progresses.
Good:
1:23/ 1:24/ 1:22/ 1:20/ 1:21/ 1:21 — trending faster overall
Great:
1:23/ 1:23/ 1:24/ 1:22/ 1:21/ 1:20 — trending faster with the bonus of finishing with the fastest interval of the day. “LOBO” stands for Last One Best One. This is not a rule but should generally be the goal of interval workouts. We want to finish strong every time.
It’s important to note that even in the “not ideal” scenario above, this is still a solid workout and the runner will make fitness gains! The splits simply demonstrate that this runner could use some more practice with pacing and body control.
Nicole Sifuentes is a full-time Running Coach for adults of all ages and abilities. She is a former professional runner and 2-time Olympian, and Certified Strength and Conditioning Specialist. Read more about her services, and schedule your free coaching consultation.