How Realistic is a Marathon Negative Split?

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Re: How Realistic is a Marathon Negative Split?

Postby jonovision_man » Thu May 05, 2016 10:27 am

Just for fun - I crunched the numbers (because I'm a geek that way).

I had to throw out some people who didn't have split times or DNF'd, so I ended up with 1337 finishers.

Of those, 60 negative split. Median finishing time for them was 3:45:13.

The rest were positive splitters. Median finishing time for them, 4:09:03.

The race winner negative split, by 11 seconds. 2nd place was +4:02, 3rd +3:48... average of the top 25 positive splitters is about 4 minutes.

I can probably geek out more, maybe I will when I have some time...

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Re: How Realistic is a Marathon Negative Split?

Postby La » Thu May 05, 2016 10:39 am

I thought we had this discussion a while ago that the "best" way was to have even splits (+/- a minute or so). Why is everyone so obsessed about the negative split?
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Re: How Realistic is a Marathon Negative Split?

Postby turd ferguson » Thu May 05, 2016 10:50 am

La wrote:I thought we had this discussion a while ago that the "best" way was to have even splits (+/- a minute or so). Why is everyone so obsessed about the negative split?


See my comment above. I think the "best" way is to run the fastest race, but I'm probably underthinking it.

ETA: I guess what I'm saying is that I get the idea of a negative split as an objective on the path to a good race, but I don't get it as a goal in and of itself.
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Re: How Realistic is a Marathon Negative Split?

Postby Jwolf » Thu May 05, 2016 12:13 pm

jonovision_man wrote:Just for fun - I crunched the numbers (because I'm a geek that way).

I had to throw out some people who didn't have split times or DNF'd, so I ended up with 1337 finishers.

Of those, 60 negative split. Median finishing time for them was 3:45:13.

The rest were positive splitters. Median finishing time for them, 4:09:03.


I agree with La-

The more relevant data would be how many were close to even within 1-2 minutes or so. These could still be positive but only slightly so.
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Re: How Realistic is a Marathon Negative Split?

Postby La » Thu May 05, 2016 12:19 pm

Jwolf wrote:
jonovision_man wrote:Just for fun - I crunched the numbers (because I'm a geek that way).

I had to throw out some people who didn't have split times or DNF'd, so I ended up with 1337 finishers.

Of those, 60 negative split. Median finishing time for them was 3:45:13.

The rest were positive splitters. Median finishing time for them, 4:09:03.


I agree with La-

The more relevant data would be how many were close to even within 1-2 minutes or so. These could still be positive but only slightly so.

Stats people, what would be the percentage of time differential where we could say that the splits were "even" for statistical purposes? I said 1-2 minutes, but that would be a more significant difference for a 2:10 marathoner than a 4:30 marathoner.
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Re: How Realistic is a Marathon Negative Split?

Postby jonovision_man » Wed May 11, 2016 1:55 pm

La wrote:
Jwolf wrote:
jonovision_man wrote:Just for fun - I crunched the numbers (because I'm a geek that way).

I had to throw out some people who didn't have split times or DNF'd, so I ended up with 1337 finishers.

Of those, 60 negative split. Median finishing time for them was 3:45:13.

The rest were positive splitters. Median finishing time for them, 4:09:03.


I agree with La-

The more relevant data would be how many were close to even within 1-2 minutes or so. These could still be positive but only slightly so.

Stats people, what would be the percentage of time differential where we could say that the splits were "even" for statistical purposes? I said 1-2 minutes, but that would be a more significant difference for a 2:10 marathoner than a 4:30 marathoner.


60 negative split

67 were positive splits within 2 mins

76 of positive splits were within 1% split of their finishing time (ie. about 2:10 on a 3h30 marathon)
170 of positive splits were within 2% split of their finishing time (ie. about 4:20 on a 3h30 marathon) (includes the 1%'ers)

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Re: How Realistic is a Marathon Negative Split?

Postby Jwolf » Wed May 11, 2016 2:26 pm

jonovision_man wrote:
La wrote:
Jwolf wrote:
jonovision_man wrote:Just for fun - I crunched the numbers (because I'm a geek that way).

I had to throw out some people who didn't have split times or DNF'd, so I ended up with 1337 finishers.

Of those, 60 negative split. Median finishing time for them was 3:45:13.

The rest were positive splitters. Median finishing time for them, 4:09:03.


I agree with La-

The more relevant data would be how many were close to even within 1-2 minutes or so. These could still be positive but only slightly so.

Stats people, what would be the percentage of time differential where we could say that the splits were "even" for statistical purposes? I said 1-2 minutes, but that would be a more significant difference for a 2:10 marathoner than a 4:30 marathoner.


60 negative split

67 were positive splits within 2 mins

76 of positive splits were within 1% split of their finishing time (ie. about 2:10 on a 3h30 marathon)
170 of positive splits were within 2% split of their finishing time (ie. about 4:20 on a 3h30 marathon) (includes the 1%'ers)

jono


These numbers are more meaningful-- thanks. I assume that the 170 positive splits above includes the shorter positive splits? If so, that says that about 17% of finishers finished with a slightly positive split or negative split, 83% with a larger positive split. That's not too surprising to me.
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Re: How Realistic is a Marathon Negative Split?

Postby jonovision_man » Thu May 12, 2016 1:34 pm

Jwolf wrote:
jonovision_man wrote:
La wrote:
Jwolf wrote:
jonovision_man wrote:Just for fun - I crunched the numbers (because I'm a geek that way).

I had to throw out some people who didn't have split times or DNF'd, so I ended up with 1337 finishers.

Of those, 60 negative split. Median finishing time for them was 3:45:13.

The rest were positive splitters. Median finishing time for them, 4:09:03.


I agree with La-

The more relevant data would be how many were close to even within 1-2 minutes or so. These could still be positive but only slightly so.

Stats people, what would be the percentage of time differential where we could say that the splits were "even" for statistical purposes? I said 1-2 minutes, but that would be a more significant difference for a 2:10 marathoner than a 4:30 marathoner.


60 negative split

67 were positive splits within 2 mins

76 of positive splits were within 1% split of their finishing time (ie. about 2:10 on a 3h30 marathon)
170 of positive splits were within 2% split of their finishing time (ie. about 4:20 on a 3h30 marathon) (includes the 1%'ers)

jono


These numbers are more meaningful-- thanks. I assume that the 170 positive splits above includes the shorter positive splits? If so, that says that about 17% of finishers finished with a slightly positive split or negative split, 83% with a larger positive split. That's not too surprising to me.


I guess... although you'd expect that almost everyone had it as a goal (even effort or negative split), so that's a lot of disappointed people at the end of the race, no?

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Re: How Realistic is a Marathon Negative Split?

Postby La » Thu May 12, 2016 1:50 pm

People will only be disappointed by a positive split if they failed to hit their finishing time goal. Some might be disappointed with a negative split, thinking that if they hadn't been so conservative in the first half that maybe they could have had an even faster finishing time.
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Re: How Realistic is a Marathon Negative Split?

Postby Jwolf » Thu May 12, 2016 2:44 pm

jonovision_man wrote:
Jwolf wrote:
jonovision_man wrote:
La wrote:
Jwolf wrote:
jonovision_man wrote:Just for fun - I crunched the numbers (because I'm a geek that way).

I had to throw out some people who didn't have split times or DNF'd, so I ended up with 1337 finishers.

Of those, 60 negative split. Median finishing time for them was 3:45:13.

The rest were positive splitters. Median finishing time for them, 4:09:03.


I agree with La-

The more relevant data would be how many were close to even within 1-2 minutes or so. These could still be positive but only slightly so.

Stats people, what would be the percentage of time differential where we could say that the splits were "even" for statistical purposes? I said 1-2 minutes, but that would be a more significant difference for a 2:10 marathoner than a 4:30 marathoner.


60 negative split

67 were positive splits within 2 mins

76 of positive splits were within 1% split of their finishing time (ie. about 2:10 on a 3h30 marathon)
170 of positive splits were within 2% split of their finishing time (ie. about 4:20 on a 3h30 marathon) (includes the 1%'ers)

jono


These numbers are more meaningful-- thanks. I assume that the 170 positive splits above includes the shorter positive splits? If so, that says that about 17% of finishers finished with a slightly positive split or negative split, 83% with a larger positive split. That's not too surprising to me.


I guess... although you'd expect that almost everyone had it as a goal (even effort or negative split), so that's a lot of disappointed people at the end of the race, no?

jono

Marathons are hard. :)

I suspect a lot of those people started off at a pace they thought they could sustain and slowed down. So yes, maybe they are disappointed- or maybe they are happy that they came close to their B goal or whatever. I'm just not surprised so many people misjudge.

Still not everyone plans pacing that carefully- and they just get what they get.
I remember when I ran my second best marathon (about an 8 minute positive split) I passed someone I knew at about 10k. I asked him how he was doing and he said "I feel great! I'm running by feel- this is awesome!" He passed me and I thought - "Wow that's great that he can run by feel- I feel like this is pretty tough and I'm trying to stick to my pace!" I ended up passing him later on and he had about a 20-min positive split. So much for running by feel! But he was still happy with his time and loved his experience.

Similarly I know several people who set out at a pace that they think they can do, but it's pretty clear to those who have more experience that they start out too fast- and end up with a large positive split. I know way more people that do this than those who run smart marathons. They just have an unrealistic time goal. Most of these people are not overly disappointed- they are just happy to finish another marathon.
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Re: How Realistic is a Marathon Negative Split?

Postby turd ferguson » Thu May 12, 2016 2:52 pm

jonovision_man wrote:
Jwolf wrote:
jonovision_man wrote:
La wrote:
Jwolf wrote:
jonovision_man wrote:Just for fun - I crunched the numbers (because I'm a geek that way).

I had to throw out some people who didn't have split times or DNF'd, so I ended up with 1337 finishers.

Of those, 60 negative split. Median finishing time for them was 3:45:13.

The rest were positive splitters. Median finishing time for them, 4:09:03.


I agree with La-

The more relevant data would be how many were close to even within 1-2 minutes or so. These could still be positive but only slightly so.

Stats people, what would be the percentage of time differential where we could say that the splits were "even" for statistical purposes? I said 1-2 minutes, but that would be a more significant difference for a 2:10 marathoner than a 4:30 marathoner.


60 negative split

67 were positive splits within 2 mins

76 of positive splits were within 1% split of their finishing time (ie. about 2:10 on a 3h30 marathon)
170 of positive splits were within 2% split of their finishing time (ie. about 4:20 on a 3h30 marathon) (includes the 1%'ers)

jono


These numbers are more meaningful-- thanks. I assume that the 170 positive splits above includes the shorter positive splits? If so, that says that about 17% of finishers finished with a slightly positive split or negative split, 83% with a larger positive split. That's not too surprising to me.


I guess... although you'd expect that almost everyone had it as a goal (even effort or negative split), so that's a lot of disappointed people at the end of the race, no?

jono


Why would almost everyone have it as a goal? The goal is the finish time.

I don't disagree that a negative split is a good strategy, but that's not the same as a goal.
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Re: How Realistic is a Marathon Negative Split?

Postby turd ferguson » Thu May 12, 2016 2:53 pm

Jwolf wrote:
Similarly I know several people who set out at a pace that they think they can do, but it's pretty clear to those who have more experience that they start out too fast- and end up with a large positive split. I know way more people that do this than those who run smart marathons. They just have an unrealistic time goal. Most of these people are not overly disappointed- they are just happy to finish another marathon.


I'd rather run another stupid 3:45 than a smart 4:15.
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Re: How Realistic is a Marathon Negative Split?

Postby Jwolf » Thu May 12, 2016 3:12 pm

turd ferguson wrote:
Jwolf wrote:
Similarly I know several people who set out at a pace that they think they can do, but it's pretty clear to those who have more experience that they start out too fast- and end up with a large positive split. I know way more people that do this than those who run smart marathons. They just have an unrealistic time goal. Most of these people are not overly disappointed- they are just happy to finish another marathon.


I'd rather run another stupid 3:45 than a smart 4:15.


That's what I'm saying-- most of these people aren't necessarily overly disappointed.

But... you could be smart and run 3:35. Running smart doesn't mean slow. If you can finish a "stupid" (big positive split) marathon at 3:45, then 4:15 isn't smart either-- it's just much slower than you are capable of.
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Re: How Realistic is a Marathon Negative Split?

Postby ABXF » Thu May 12, 2016 3:56 pm

This is a forum about trying to feel good about yourself, not about understanding things. According to popular running culture, positive and negative splits both make good excuses so are quite relevant here. The topic of the best strategy for finishing time is less relevant on this forum.

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Re: How Realistic is a Marathon Negative Split?

Postby ABXF » Thu May 12, 2016 4:11 pm

For example, if you come in 30 minutes slower than you expected with your excellent confidence, it wasn't because you didn't have it in you in terms of fitness or because you came apart psychologically like a small child when you started slowing down, it is because you went out too hard.

Another example. You have no talent in anything and really need to make running your thing. Your faith in it actually being meaningful is often challenged so it's important to really score high, like winning your age group in a marathon but after putting your all into it for several years, you are still 10 or more minutes short. Meanwhile, the top age group placer runs some absurd positive split. No problem, they ran stupid and you are the talented one.

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Re: How Realistic is a Marathon Negative Split?

Postby turd ferguson » Fri May 13, 2016 11:21 am

Jwolf wrote:
turd ferguson wrote:
Jwolf wrote:
Similarly I know several people who set out at a pace that they think they can do, but it's pretty clear to those who have more experience that they start out too fast- and end up with a large positive split. I know way more people that do this than those who run smart marathons. They just have an unrealistic time goal. Most of these people are not overly disappointed- they are just happy to finish another marathon.


I'd rather run another stupid 3:45 than a smart 4:15.


That's what I'm saying-- most of these people aren't necessarily overly disappointed.

But... you could be smart and run 3:35. Running smart doesn't mean slow. If you can finish a "stupid" (big positive split) marathon at 3:45, then 4:15 isn't smart either-- it's just much slower than you are capable of.


That wasn't one of the choices. The choices were "fast" or "smart" and you picked "fast and smart".

Running smart doesn't mean running slow, I agree. But running smart isn't a goal in and of itself. Fast is still the goal.
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Re: How Realistic is a Marathon Negative Split?

Postby Dstew » Mon May 16, 2016 12:14 pm

turd ferguson wrote:
Jwolf wrote:
turd ferguson wrote:
Jwolf wrote:
Similarly I know several people who set out at a pace that they think they can do, but it's pretty clear to those who have more experience that they start out too fast- and end up with a large positive split. I know way more people that do this than those who run smart marathons. They just have an unrealistic time goal. Most of these people are not overly disappointed- they are just happy to finish another marathon.


I'd rather run another stupid 3:45 than a smart 4:15.


That's what I'm saying-- most of these people aren't necessarily overly disappointed.

But... you could be smart and run 3:35. Running smart doesn't mean slow. If you can finish a "stupid" (big positive split) marathon at 3:45, then 4:15 isn't smart either-- it's just much slower than you are capable of.


That wasn't one of the choices. The choices were "fast" or "smart" and you picked "fast and smart".

Running smart doesn't mean running slow, I agree. But running smart isn't a goal in and of itself. Fast is still the goal.



But what does "SMART" actually mean?

In 2005 "smart" meant ripping my body apart in order to make a good effort to qualify for Boston. Given a number of issues I faced, I knew there were only a limited number of legitimate shots at that particular brass ring. But was it "smart" for my long term running and/or health?

In 2007 the raison d'etre for all of the time, money and effort to run Boston again was at the very least running a faster Boston then the year before and breaking the 3:30 barrier as well. My training and race were "smart" for those goals but half way through the race I came to realize how "stupid" those goals were.

I believe I ran smart marathons in 2012, 2013 and 2014. The first two, I pushed my pace based upon what my training and the current state of my body would allow but I was still damn sore following those two races. In 2014, I was doing the same thing but my mind, body and soul told me at the 5 K mark it was not worth doing. I had a round of golf the next day, a full day business meeting and plane flight the day after and so I "smartly" reduced my pace. Although my body was relatively unscathed as a result, emotionally and psychologically it felt like a very long training run and there was almost no sense of accomplishment or achievement. I was haunted by the question of why bother but on the other hand, to have made an effort to reach a certain ethereal goal, I would have paid a physical price. So what was the smart choice?

So again, what is "smart"?

In this context, I would argue smart and fast are essentially the same thing. There is the obvious "dumb" tactic of running so hard one has to walk in or worse, visit the medical tent. But running too slow may not get one to Boston or to a certain level of satisfaction?

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Re: How Realistic is a Marathon Negative Split?

Postby Jwolf » Mon May 16, 2016 3:47 pm

To me running a "smart" marathon was simply short-hand for the question at hand-- evenly paced. That is, the best possible pace you can run without slowing down. I still believe that is the FASTEST and smartest way to run a marathon. So yes, running "smart" may not be the goal in itself but it's the way to the goal.

Many on this board have done it.
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Re: How Realistic is a Marathon Negative Split?

Postby Dstew » Tue May 17, 2016 10:03 am

Jwolf wrote:To me running a "smart" marathon was simply short-hand for the question at hand-- evenly paced. That is, the best possible pace you can run without slowing down. I still believe that is the FASTEST and smartest way to run a marathon. So yes, running "smart" may not be the goal in itself but it's the way to the goal.

Many on this board have done it.



I agree that one cannot run a "fast" marathon without running a "smart" marathon whereas with shorter races one might be able to get away with being dumb. Although there is a argument that to run the fastest race of any distance requires at least some smart.

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Re: How Realistic is a Marathon Negative Split?

Postby ABXF » Thu May 19, 2016 12:07 pm

Jwolf wrote:To me running a "smart" marathon was simply short-hand for the question at hand-- evenly paced. That is, the best possible pace you can run without slowing down. I still believe that is the FASTEST and smartest way to run a marathon. So yes, running "smart" may not be the goal in itself but it's the way to the goal.

Many on this board have done it.


+36000

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Re: How Realistic is a Marathon Negative Split?

Postby ABXF » Thu May 19, 2016 12:12 pm

CONSISTANCY is key.


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