Are Even Splits for a Marathon common? Possible?

[Patrick Kearney]

I was wondering if anyone knew about what percentage of the time someone achieves even splits throughout a marathon.  Or even close to even splits.

[Jon Allen]

According to Pete Pfitzinger and science, an even-effort on a flat marathon will result in 1-3 minute second half slowdown (for 2:30-4hr marathoners).  Read about it here:
http://runningtimes.com/Article.aspx?ArticleID=17908

And yes, it can be done but it requires A) having a very realistic goal, and B) having the patience to start out slow enough.

[Bonnie]

I did it ... but I was actually running a little slower than I realistically could have (because it was my first one and I wanted to make sure I finished).  I am glad I did it that way though, since even though I am a "negative splitter" I was seriously overwhelmed the last 3 miles of the marathon!!  In my next marathon (if I ever get healthy enough to run another) - I plan to "even split" again, I think everyone is different - I personally don't ever like to slog through the last part of a race ... no matter how much faster I might run overall to do it (I am a baby that way ;-) ).

I do think that realistic goals are a necessity, probably regardless of whether you want to run even splits or not.  Probably why a good solid 1/2 marathon about a month out from the marathon is a good idea ...

[Paul Petersen]

There no reason why you can't even split, or be close at least. A big positive split indicates either poor training and/or a bad race-day strategy. It's not how it's supposed be.

I've been on both side of even, and it's by far more fun to be slightly positive, even, or negative. My first 5 marathons were big positive splits, and were quite painful, with disappointing finish times. With the exception of one stinker of a Des News race, my last 8 or so marathons have been close to even splits, an outcome mostly due to improving my training plus having more realistic time expectations.

[Paul Petersen]

I do think that realistic goals are a necessity, probably regardless of whether you want to run even splits or not.  Probably why a good solid 1/2 marathon about a month out from the marathon is a good idea ...

This is incredibly true.

[Sasha Pachev]

Patrick:

I do not have the statistics, but I would intuitively guess that on average the second half of a marathon is 15 minutes slower than the first. That said, we must clarify that were are talking about a non-elite marathon. The average sub-2:30 marathon for a male statistically has around 3 minute positive split. The average sub-2:10 marathon would have no more than 1 minute positive split. That is because you have to be awfully fast to be able to run the first half and still live if you can positive split and still run to 2:10. A positive split of 2 minutes means you have to go through the first half in 1:04, and just to be able to run one half in 1:04 requires a combination of high efficiency and endurance, something that greatly contributes to the ability to run an even or negative split in the marathon without jogging the first half.

Note that it is always possible to really bum the first half, and get a negative split, even on a bad day. A 2:40 marathoner will  negative split even on a bad day he opens with a 1:35 half, for example, but his time will be around 2:53 on a good day.

So the trend is the faster you are the more negatively you split. However, forcing a negative split will not make you faster. My suggestion is to train diligently and let the split come due to fitness rather than pacing. The dirty little secret is that when you are really fit, the ideal marathon pace is so strenuous that you really have to focus hard to hit it and will not exceed it without getting some serious messages from the body.  Your body will learn how to run optimally and you will be surprised at how lively you are compared to how you used to be in the closing miles of the marathon.

[Rick]

According to Pete Pfitzinger and science, an even-effort on a flat marathon will result in 1-3 minute second half slowdown (for 2:30-4hr marathoners).  Read about it here:
http://runningtimes.com/Article.aspx?ArticleID=17908

And yes, it can be done but it requires A) having a very realistic goal, and B) having the patience to start out slow enough.

Good topic. I think for me, as a slow runner, another factor is the temperature increase during the race, that you fast people get to miss out on.
Can I ask a related question: if I would try Pfitzinger's recommendation, to get a 3:35:00 time, I would run the first half in 1:46:00 (8:05 min/mile) and the second half in 1:49:00 (8:19 m/m). So, then when I would do training runs that include some miles at "goal marathon pace", should that be 8:05?

[Jon Allen]

Good question.  Yes, I would look at 8:05 as the marathon pace.  8:19 is the "slow down" marathon pace.  But if you can't do workouts geared towards your 8:05 pace, you won't be able to run it in the race.

[jtshad]

Yes, it is realistic on a flat course, but it does require some patience during the first half and good endurance and training to help you through the second half.    At the B&A Trail marathon in March 2010, I ran a 2:40 with less than a minute positive split (just under 1:20, just over 1:20).  I went out nice and controlled for the first 5 miles then started to pick it up around mile 6 and tried to maintain that pace through the end.  The last 3 miles I slowed due to a bit of cramps and knowing that I had a 4-5 lead on the next guy so mentally I went from race to finish mode.   I did have to just hold back and run easy the at first and I had trained well to maintain a good pace throughout the race.  Probably the best pacing race I have run (especially since it was not an aided course) so it can be done with the right strategy in mind.