Even if you haven’t mastered the process, you have probably heard about “negative splits” when it comes to racing. It’s hard to execute even for the most experienced runners, but this pacing strategy often results in PRs and world records when perfectly implemented into your racing plan. For example, when Emily Sisson set the current American marathon record at the 2022 Chicago Marathon, she ran a slight negative split, finishing the first half in 1:09:26, and the second half in a slightly faster 1:09:03.
But negative splits aren’t reserved just for elite runners. Anyone can run negative splits—in a marathon, in a half, or a race of any distance—with a little bit of patience and some practice. And although the idea of speeding up later in the race may sound unattainable, it’s something all runners can practice in order to crush their plan on race day.
Let’s break it down.
What are negative splits?
Negative splits are a pacing strategy that involves running the second half of a run or a race faster than the first half. The goal is to start slower than your goal pace and gradually increase your speed.
The opposite of negative splits is running positive splits, which tends to happen to a lot of runners when they go out fast and slow down later in a race. Another option is aiming to run even splits, where you maintain the same pace throughout a run.
Why should you aim for negative splits?
Negatively splitting your race can have a positive impact on both your physical and mental performance. When it comes to your body, it’s easier to run faster once it warms up.
“Starting a race more conservatively can help with overall energy efficiency by conserving energy and glycogen stores early in the race,” says Jessica Schnier, the founder and coach at Smiles & Miles Coaching in San Diego, California. “By not burning through those stores too early, a runner is able to finish stronger, allowing the body to progress into faster paces, which helps increase the pace more efficiently.”
Your mind benefits from negative splits just as much, helping you stay motivated to keep racing, says Jenni Nettik, owner and coach at Mercuria Running in Colorado. “Finishing a race feeling strong and running fast is more fun and encouraging than struggling through the final few miles of a race, or crawling across the finish line,” she adds.
How do you negative split your race?
Start with setting a goal time for your race and work from there. You can use your recent workouts to predict a reasonable time you can achieve (as you do want to set yourself up for success) or a previous race as a barometer. This running pace calculator can help you predict your race pace, and using pace charts can help you figure out your goal race pace.
For example, finishing a half marathon in under two hours means running at 9:09/mile pace; if you want to run negative splits, you may run the first half, say, two minutes slower than the second half, which would mean maintaining a 9:16 to 9:20 minute/mile in the first half to cross the halfway-point at 1:01, then increasing your pace a little each mile to 8:58 to 9:02 minute/mile to reach the finish line in under two hours.
It’s always important to keep fueling top of mind when it comes to longer races like a half marathon or marathon. With negative splits and a conservative early pace, you may not feel hungry right away. “Fueling early and often, before you feel like you need to eat, keeps glycogen consistent, so the body has the energy it needs to increase the effort in the second half of the race,” Nettik says. “If you don’t fuel, you won’t have the energy to run negative splits and your brain will try to conserve energy by slowing down.”
Are negative splits reserved only for racing?
“Nothing new on race day” is a motto that applies to your racing strategy as well as your gear, so if you decide you’ll be gunning for a negative split, you should practice holding back and pacing yourself during long runs in training.
“The advantage of targeting this would be that it encourages the runner to practice patience at the beginning of a run when they feel their best, which is a useful strategy to have in both training and racing,” Schnier says. “This can also be a confidence booster at the end of runs, which can feed into the many positive psychological benefits of finishing a run strong.”
Whether you’re training for a race or not, negatively splitting your next runs can help you get back on track mentally, if your running confidence has been dwindling.
How do you practice negative splits?
The secret to negative splits is starting way slower than you think you should (to figure out your easy pace, use this calculator). To practice that, try these beginner-friendly, negative-split workouts on your next run. These workouts are meant to help you get a feel for finishing up faster than you started, so overall time isn’t the goal. Include at least a 10-minute or one-mile warmup in these workouts, and a 10-minute or one-mile cooldown, followed by a few postrun cooldown stretches.
🏃 Strong close:
Nettik says you could do a four-mile run, with the goal to do the final mile faster than the first three. Remind yourself that it’s okay for the last mile to feel hard. With this run, go more by feel and focus less on the metrics your watch shows you.
- After warming up, run the first three miles at a conversational pace that feels truly easy to you.
- For the final mile, push your effort and bring the pace down, finishing as fast as you can.
🏃 Progression run:
Nettik also suggests trying a 3-mile progression run, bringing down your pace by 1 minute every mile after warming up. This type of cutdown run helps you feel the difference between paces.
- Mile 1: 2 minutes slower than your goal pace
- Mile 2: 1 minute slower than your goal pace
- Mile 3: Your goal pace
🏃 Negative split ladder:
Schnier recommends doing a ladder workout starting at 10K pace and ending at 5K pace, followed by a cooldown.
- After a warmup, run 5 minutes fast with a 2-minute easy run before the next interval. Repeat that with a 4-minute, 3-minute, 2-minute, and 1-minute fast interval with 2 minutes of recovery after each.
- Start the 5-minute fast intervals at 10K pace (approximately 10-30 seconds slower than your 5K pace).
- Progressively increase the pace by 4-6 seconds per interval, ending at 5K pace or slightly faster by the 1-minute interval.
Are there instances when negative splits are not recommended?
It’s important to look at the course profile before the event to consider what the best pacing strategy will be, Schnier says.
“A course with a lot of hills or with significant elevation change may require different pacing strategies, such as an even or positive split, to help create the best result,” she says.
Nettik recalls specific instances when she recommends her athletes choose positive splits, including Revel marathons, which are known for having fast downhill courses.
“Many of the Revel races start steeper and level out as the race continues,” she says. “Slowing down during the steepest [downhill] parts of the race would cause more stress on body/quads, making it difficult to increase the effort or pace in the second half of the race. While starting faster, the effort is still easier and breathing is calm.”
Another example when positive splits may be the better option is an increase in temperature throughout the course.
“I had runners doing the Utah Valley Marathon in 2021, and there was a heat warning for the region,” Nettik says. “The race started early in the morning at elevation, when and where it was cooler and finished at a lower elevation in town where the temperature was anticipated to be much higher. It was a hilly course, so on a cool day, I’d have recommended negative splits. However, due to the heat, I advised my runners to run faster while it was cool to beat as much of the peak heat as possible, knowing the conditions were going to be difficult at the end.”
The Bottom Line on Negative Splits
In the end, choosing the right racing strategy depends on a few factors, including the course elevation, the weather conditions, but also your goals. Practice executing negative splits on your training runs to see how your body and mind feel during and afterward. While negative splits are a great strategy used by many athletes around the world, it’s not the only pacing strategy out there, so make sure you do what’s best for you.
Pavlína Černá, an RRCA-certified run coach and cycling enthusiast, has been with Runner’s World, Bicycling, and Popular Mechanics since August 2021, joining originally as a newsletter editor. When she doesn’t edit, she writes; when she doesn’t write, she reads or translates. In whatever time she has left, you can find her outside running, roller-skating, or riding to the beat of one of the many audiobooks on her TBL list.
