Ok. I’m trying to decide how to pace my marathon this weekend. My goal is 3:25:00. I’m a bigger runner (44 yo., 5’10", 175), and I tend to do better on long runs when I start slower and neg split the second half. Trying to decide how deep into the well I can dip and still have a chance at 3:25:00. Recent 5k is 20:28, HM 1:39:00. My most recent long run was 18 miles with last 8 at 7:40/mi and I had enough in the tank to run another 8. I know it’s going to be tight. Would you try and run even 7:50’s or Neg split? I was thinking 1:44:00/1:41:00. Too much?
Aim for dead even pace.
I’ve never been able to negative split an Ironman marathon. I have almost even split it, though usually my last 10K is slower. By 20 miles, I’m simply struggling to survive!
-Robert
How many marathons have you run? If this is your first I agree with the previous poster, try for an even split. Running a negative split, at least in my case is a lot harder than it sounds,and that was especially true for my first few marathons. As good as you felt on your last long run what happens mile 22 and up is sometimes hard to predict.
Good luck, hope you hit your goal.
Mike
I’ve read a research paper before on glycogen stores and marathons and based on their studies, for fueling reasons, it’s better to run an even pace than a negative split. Bonking is worse with the negative split.
You should shoot for a slightly negative split (1-2minutes) and I can pretty much guarantee you that unless your course is hilly up then hilly down in each half (the San Francisco marathon lends itself to a surprisingly big negative split), you’re going to still slightly positive split it.
Running a negative split in a marathon is devilishly hard if you’re shooting for a PR and not just running under your ability.
You should shoot for a slightly negative split (1-2minutes) and I can pretty much guarantee you that unless your course is hilly up then hilly down in each half (the San Francisco marathon lends itself to a surprisingly big negative split), you’re going to still slightly positive split it.
Running a negative split in a marathon is devilishly hard if you’re shooting for a PR and not just running under your ability.
Ditto. I recommend most people try for the Negative Split and usually it means they don’t bonk as hard in the second half and get much closer to “even”. So in the end “even” pacing is what you get by shooting for negative.
Most people I know who start out to run “even”, think they are running a pace they can hold. It’s comfortable but too fast. In the end, they add 5-10 minutes in the last 6-8 miles.
Ok, so you’re saying then for me that I should start out with the idea of running 1:43:00 going out, 1:42:00 coming in and most likely I’ll end up around 1:43:00/1:43:00-1:45:00 and run 3:27:00ish? If I have a great day I’ll negative split and hit my goal.
Ok, so you’re saying then for me that I should start out with the idea of running 1:43:00 going out, 1:42:00 coming in and most likely I’ll end up around 1:43:00/1:43:00-1:45:00 and run 3:27:00ish? If I have a great day I’ll negative split and hit my goal.
Yes.
I might even be more conservative than that if the course profile is flat or equal elevation change in 1st/2nd half. The more of a beginner you are at this, the bigger your differential should be if you’re planning to run a equal split.
I’d recommend for true marathon 1st timers, even well trained ones, to plan to run 5 minutes slower in the 1st half versus the 2nd half split (but don’t just ramp up the 2nd half split time to some crazy fast pace just to make the numbers hit your target.) Given that a strong showing for a beginner marathoner (who wasn’t a really good competitive runner previously), would be a <5 minute bonk at the very last mile, I think 5 minutes is still not overly conservative. Your odds of bonking by 7-15+ minutes are extremely high as an ambitious 1st time marathoner. Like over 50%, I’d venture to say.
First tell me about the marathon. Is it flat? Hilly? It’s easy to pace a flat one. I don’t know if it’s a good idea to be tied to a pace on a hilly one tough.
My best ever marathon was also my only negative split marathon. But the only difference between it and all my other good marathons was that I never hit the wall. So my last 3 miles were fast, not slow.
The general rule of thumb is take your half marathon, double it and add ten minutes. And that’s assuming a) nothing goes wrong and b) you have all the mileage you need for the marathon and c) nothing goes wrong and d) nothing goes wrong… Then your goal is chopping another 3 minutes off that.
Ok. I’m trying to decide how to pace my marathon this weekend. My goal is 3:25:00
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I was thinking 1:44:00/1:41:00. Too much?
I would think the split is too wide. 1:43/1:42 is more realistic and definitely possible (assuming you have the fitness).
I’m running the Denver Rock and Roll. Flat for Denver and I live here so I’m used to the elevation. I haven’t run an open marathon in 15 years but have done an IM , a half IM and two HM’s this year. My run was 4:07:00 at CDA (walked a lot of last three miles.), two 1:40:00 HM’s in the spring, one of them flat with horrible weather, one of them with a 400ft climb. My most recent race was my HIM. My split was 1:47:00 on generally flat course.
As some have already pointed out you want to slightly negative split the marathon assuming the course is similar on both halfs. I have heard it said that for every minute you run too fast on the first half you lose 2 minutes on the back-half. If you are confident that you should be able to run a 3:25 then run the first half in 1:43ish and then pick-up the pace a little for the back half. A good strategy to use is to break the race into sections. Start off by breaking the marathon into two pieces. Once you complete the first piece (ie. the first half) then break the second half into two pieces again (ie. 21.1-32 kms or 13.1-20miles and 32-42.2kms or 20-26.2miles). Run the second piece at your adjusted pace (ie. in your case slightly faster). Once your at 32kms or ~20miles break the last 10km or 6 miles into two pieces again. If you know you are still feeling good at 32kms or 20miles bump the pace up slightly more. Once you reach 37kms or 23miles it’s time to make a final call. If you’ve got fuel left in the tank bump the pace up and push the last section to perhaps even do better than your goal. If you’re feeling spent hold the current pace and focus on your splits to bring you in at your goal pace.
That’s how I pace my runs regardless if it’s a Marathon or Half-Marathon.
Go out with a mindset targeting an even split. Pick the goal (3:25) you want to hit, then pace (7:49) at that goal… then at mile 23.1, if you feel like you can run a faster than (7:49) pace final 5k, go for it at that time. My best marathon was a negative split by 1 minute, but the majority of my marathons were even splits, that I was very happy about.
Bottom line answer is that you can’t really decide to go for a negative split and expect to be successful. It just has to happen based off of how you feel and whether you picked an aggressive enough goal in the first place. If your goal is aggressive enough, then even split is the smartest way to get there.
Be sure to report back on how it goes.
I agree. Running a marathon at even pace is best, but most who actually do run even tried to negative split and failed.
Whenever I hear people say that they finished strong, but wish they had gone out faster I think, “Next race you’re in trouble”
Whenever I hear people say that they finished strong, but wish they had gone out faster I think, “Next race you’re in trouble”
Because those people don’t realize the biggest mistakes they can make are in that opening 5 and 10k.
Those who try to negative split set themselves up for failure. Muscle fatigue is like the honey badger, it doesn’t give a shit how much you sandbagged the first half of the race. Run even…
My last and only marathon I did a negative split. I went out at a 3:07 pace and with 10k left I was certain I wasn’t going to hit a “wall” so I dropped the hammer and finished in 3:04. My next marathon which is in about a week I plan on using the same strategy only I will finish 4 minutes faster.
One more thing. I negative split every training run I can remember for the last 6 months. I don’t have easy runs or tempo runs. I try and take every run like it’s a race and my pace is normally at or below my marathon pace.
This may not be for you but it seems to work for myself.
Whatever works for you, but that’s not normal. I’ve run over 20 marathons with most in the 2:40’s or faster. In my experience, people negative splitting by a big amount of time are usually leaving time on the course.