The first marathon I ever ran was the Vermont City Marathon in Burlington, Vermont. It was 2009, and I had just gotten out of college.
Surprisingly, I didn’t have a goal time in mind, but I admittedly crashed and burned after going out too hard. I eventually finished at 3:19:20, which is certainly a respectable time for a first-time marathon finish, but it wasn’t a pretty race.
There was a lot of walking, and I ran some of the worst positive splits you’ve ever seen (the second half of the race was significantly slower than the first half-marathon portion).
I took home my finisher’s medal with pride, but I also vowed to work on my marathon pacing strategy for my next race, hoping to run a new PR.
My goal was to run negative splits, which is exactly what I did. I crossed the finish line of the New York City Marathon that same November at 3:01:02, feeling so much stronger throughout the whole race and setting a new personal record for the marathon.
So, do you want to finish your race feeling strong? Learn how to master negative splits, pace smarter, and run your fastest half marathon, marathon, or 5K yet with this expert guide to race-day strategy!
What Are Negative Splits?
Negative splits are a pacing strategy where you run the second half of the race distance faster than the first half, so you pick up the pace as you run.
For example, if you aim to finish a 10K in 45:00, you might run the first 5K in 23 minutes and the second 5K in 22 minutes.
Even splits mean that you maintain roughly the same average pace throughout the entire race.
For example, if you want to run a 4-hour marathon finish time, even split pacing means that your half-marathon split would be two hours because the second half-marathon would also be two hours (an even pace).
Positive splits mean that you run the second half of the race slower than the first half, as I did in my first marathon.
In other words, the positive split strategy involves going out hard and then slowing down over the course of the race.
What Is The Best Pacing Strategy?
Although running negative splits isn’t the only viable pacing strategy for long-distance races, some of the best race performances1Bossi, A. H., Matta, G. G., Millet, G. Y., Lima, P., Pertence, L. C., de Lima, J. P., & Hopker, J. G. (2017). Pacing Strategy During 24-Hour Ultramarathon-Distance Running. International Journal of Sports Physiology and Performance, 12(5), 590–596. https://doi.org/10.1123/ijspp.2016-0237 have been executed with the negative splits pacing strategy.
Indeed, the negative splits strategy has been used to set some Olympic gold medals in distance races and running world records.
For example, the late Kelvin Kiptum set the marathon world record at the 2023 Chicago Marathon where he triumphantly crossed the finish line in a time of 2:00:35.
Kiptum broke Eliud Kipchoge’s marathon world record time (2:01:09) by a full 34 seconds.
In the 2023 Chicago Marathon, Kiptum’s average marathon pace was around 4:36 min/mile or 2:51 min/km compared to Kipchoge’s pace of 4:37.4 min/mile or 2:52 min/km at the 2022 Berlin Marathon when he ran 2:01:09.
The average paces only tell part of the story of how each of these men’s marathon world record races unfolded.
Kipchoge’s race strategy was to go out hard, maintain a fast pace, and hang on to finish the race as fast as possible, running fairly even splits.
In his tragically short marathon career, Kelvin Kiptum established himself as a strong closer, running negative splits—a slower first half and a faster second half.
Indeed, when you compare the marathon race performances in these two world record-setting races, Eliud Kipchoge ran fairly even splits while Kiptum executed tremendous negative splits, with the first half in 60:45 and the second half in 59:50.
Running negative splits also works for shorter races.
For example, Galen Rupp2Galen RUPP | Profile | World Athletics. (n.d.). Worldathletics.org. https://worldathletics.org/athletes/united-states/galen-rupp-14250207 set the American Record in the indoor 5K by running the first mile in 4:13, the second in 4:12, and the last in 4:04.
What Are the Benefits of Negative Splits?
Every race pacing strategy has benefits, so there isn’t necessarily a single best strategy in all situations.
As a running coach, I often encourage beginners or experienced runners who are trying a longer distance race for the first time to aim to run even splits.
Even pacing helps you conserve your energy,3Cuk, I., Nikolaidis, P. T., Villiger, E., & Knechtle, B. (2021). Pacing in Long-Distance Running: Sex and Age Differences in 10-km Race and Marathon. Medicina, 57(4), 389. https://doi.org/10.3390/medicina57040389 allowing you to feel strong throughout the duration of the race without getting anxious that you aren’t going to hit your goal finish time because you are starting at a slower pace.
However, if you practice negative splits in your training plan leading up to the race so that you have confidence in your ability to pick up the pace in the last half even when you’re tired, you may end up setting a new PR when you can execute a negative split strategy.
Here are some of the benefits of running negative splits:
- Conserves energy in the first half of the race so that you don’t tank in the last mile (or even the last half!) of a race.
- Can boost your moral or mental strength on race day because you feel stronger and run faster in the second half rather than tiring out because you have gone out too hard. You can also pass other runners who are struggling, which can increase your motivation and confidence.
- Starting out slowly helps you warm up as the first couple of miles in a long race unfold. For half marathon and marathon races, this can reduce the need to do an actual warm up before the race, which helps preserve your glycogen stores and energy levels. Plus, if you don’t do a proper warm-up and you run a positive split, especially for shorter races where you are going out at a fast pace, you may increase your risk of injury because your muscles and connective tissues are not properly warmed up before high-intensity fast running.
How Do You Run Negative Splits?
Here are some tips that can help you run negative splits in your next race:
#1: Practice Running Negative Splits Throughout Your Buildup
For some runners, running negative splits comes fairly naturally because they like to run the first mile of a race conservatively to warm up.
For other runners, the excitement and adrenaline as a gun goes off and the throngs of competitors sprinting through the first mile can make it difficult to rein it in and not run the first half of the race too fast.
If you fall in the latter group, you will want to practice the negative splits strategy in your workouts.
Using some of your longer training runs in the buildup to the race is a good strategy to practice running negative splits. Typically, the best workouts to practice running negative splits are progression runs and fast finish long runs.
With a progression run, you gradually pick up the pace over the course of the run.
Progression long runs to prepare for a half marathon or marathon are the perfect opportunity to work on running a faster second half for race day.
A fast finish long run can also be helpful.
Here, you would do most of the long run at your easy long run pace and then run the last mile hard—at race pace or faster.
#2: Use Your Watch
Although many road races and track races have mile markers or time clocks for each lap, wearing a GPS running watch will give you instantaneous running pace and your average splits.
This puts the control literally in your hand so that you can adjust your race pace accordingly.
In the competitive atmosphere of an actual race, we often run faster than we think we are running, getting pulled along by the energy of the spectators and fellow runners.4Tomazini, F., Pasqua, L. A., Damasceno, M. V., Silva-Cavalcante, M. D., de Oliveira, F. R., Lima-Silva, A. E., & Bertuzzi, R. (2015). Head-to-head running race simulation alters pacing strategy, performance, and mood state. Physiology & Behavior, 149, 39–44. https://doi.org/10.1016/j.physbeh.2015.05.021
Particularly if you tend to run the first mile or first half of a race too quickly, checking your watch every quarter mile in the first mile and every half mile over the next couple of miles can help ensure that you are holding yourself back and running the appropriate pace for negative splits and your ultimate goal finished time.
#3: Run Strides After Easy Runs
Consistently running strides after easy runs or short workouts is a great way to build up leg speed and turnover.
Even if you run relatively even splits on race day, if you have a strong finishing kick, you can still cross the finish line with overall negative splits!
What pacing strategy has been most successful when you have run a new PR?
To work those progression runs into your training schedule, check out our next guide:
Hi Thomas, Well I finished my first ever marathon yesterday at age 55. I started this journey with the goal of breaking 5 hrs. and started 16 weeks ago following your training plans and guidance. All of the information you shared in your Master Class was helpful. Through injuries (shin splints and my back seizing up in the final week of the Taper), I managed to hit the start line and kept thinking of your one of your main strategies of not going out too fast and keeping a constant pace. Here is a question: When the Long Runs each week specify to go Easy and your advice is that they should be 30-90 seconds slower than the race pace, how do you know then what “Easy” should be. I was able to run the longest run (21 miles) at a 11:26 pace and then thought I could run a “race pace” at 10:15 -10:30. Long story short… I started off and did exactly what you said NOT to do – go out too fast… I got to mile 15 and it all started to go downhill. I went from running an average of 10:15 to a 2nd half of 12:40. I just don’t know was “Easy” means on the long runs… With it being my first marathon now I know what to expect and should have gone out slower (10:45 or above)… Advice?
Hey Jesse,
Good to hear from you and great work on the marathon!
My general advice for knowing how ‘easy’ a long run should be – if it feels like you’re exerting yourself, slow down! In other words, sit at a comfortable 2-3 out of 10 for RPE (my guide to RPE may be of interest to you). .
Hope that’s of some help!
Thomas
My best half and my only marathon so far I started the race thinking I was injured and not even expecting to finish. In both cases this meant I ended up running negative splits and I improved my half’s PB by 10min and running the marathon a good 20minutes faster than I anticipated (in 4:34). The half marathon I could have been even faster and gone sub 2 but there was too much human traffic in the last 2 miles. Overtaking gives you a psychological boost, but having to wave in and out of slower runners and walkers takes its toll. So make sure you know whether the last part of the race has wide roads. In both cases the first 2 and 5km were run around 6:30min/km or slower.
But when I implemented this strategy by design (ie I didn’t think I was injured) and created a negative split plan on my watch to adhere to, I found I couldn’t keep up the planned faster pace in the last mile or so. This was a half marathon and the last mile was supposed to be 5:35min/km. I just didn’t have the energy.
So, in a nutshell, I am a big fan of the negative split strategy. It’s always given me good results. But it’s a bit tricky to judge the exact extent of the speed-up surge and what to aim for your fastest split and for how long you can maintain it when fatigued. Plus nutrition and hydration are key. You need to load up in the first part of the race. In the marathon after km 36 I got stomach cramps and couldn’t face the last gel, I think that affected me, my worst split was around km 40. I stopped, caught my breath, and run the last 2km to the finish, but could have been better/faster.