Average marathon splits

Hi, just interested in gaining information regarding marathon splits.  Negative/even splits are obviously the optimum in current racing and while common in elite running, alot of us struggle with this.  I've read that 3-5 minutes would be a respectable postive split and just wondered where everyone else fits into this.

My 2 marathon bests have both had a positive split of around 8 minutes (15 minutes seperates the two times).  I set myself 3 targets - something I'd be really,really happy with but is probably too optimistic (but not according to the race time predictor), a time that is definitely achievable and a worst case scenario which will still be quick enough for me not to give up running.  I start off at the pace for the best case and then start to slow.  I don't think that if I started out the pace for my middle target and tried to speed up that I would ever make the time back up... 

Go on, show me your splits!

negative splits are not always possible - just a best case scenario.

I tend to run off road hilly races so it depends a lot on where the hills come in a race. I've not run Beachyhead but I know full well that I could never run the second half as fast as the first - the steps and the 7 sisters would kill me - I walk them as I find them too steep to run up. This is just an example - I've ran races where all the uphill is in the first half and the downhill in the second - running down hill for over 2 miles does wonders for your splits.

I would assume from your points that you are setting out too fast and that your targets are somewhat over optimistic for your training.

OK - a marathon maybe too long a distance to experiment with so I suggest that you trial with hm - run the first half slower than your target, then speed up slightly - then speed up some more. You'll find that instead of running out of energy you'll have reserves to draw upon.

Forever Hopeful wrote (see)

Negative/even splits are obviously the optimum in current racing and while common in elite running, alot of us struggle with this. 

Whilst running a negative split is hugely satisfying and generally feels more comfortable (mentally and physically) than a positive one, I don't think it's obviously optimum in terms of fastest achievable time.  I think there's an argument to suggest that a small positive split may be optimum, based on the idea that even pacing is all well and good, but over the marathon distance fatigue becomes harder to overcome in the latter stages; if you've managed a negative split, harsh as this may seem, maybe you started out too slowly (from the point of view of running as fast a time as possible.) 

Maybe things are difference for elites, i.e. just over two hours of racing for someone who trains 140 mpw may not be hard enough for the effects of fatigue to affect the even pacing strategy, and the fact that the world's fastest times are generally negative splits is down to the fact that the pacers go out at blistering pace, yet the world's best marathon runners still have enough running in them to race the second half.  Just a thought.

Anyway, since you ask...

2007 FLM  1:30 / 1:34 = 3:04 : 4 mins positive split
2008 Paris  1:22:30 / 1:21:30 (ish) = 2:44 : 1 minute negative split
2009  Beachy Head  1:30 / 1:39 = 3:09 : 9 mins positive split

Notes:
London: gunning for sub-3, was always slightly behind the pace, not helped by heat and soaring heart rate, could probably have squeezed out a 3:02 if I wanted to kill myself but eased off at 22 miles when I realised sub-3 wasn't on.
Paris:  target: sub-2:45.  Textbook pacing with a little left in the tank, if I do say so myself.
Beachy Head:  the second half is f*cking hilly! 

Thanks IM - in fairness, if the training schedules are to be believed, I was literally bang on target for the my first target. The second half was probably more undulating than the first and I think I suffer pyschologically as when it gets hard I always then just settle for beating my next target and I probably slow more for all the thoughts going in my head. Interestingly, or not, I set a PB for the half distance this year too and again I changed my goal in the last 3 miles and was just going to settle for a different time, another lady then overtook me with two miles to go and I decided to just stay as close to her as possible and not think about the time, which meant I was running 40 seconds a mile faster than I'd just decided for the last two (and it didn't feel bad!) ... So, on a favourable day, if you were running a flat marathon what split would you expect?

PP - 2.44 ... textbook indeed!! Your 3.04 fits in with the theory of 3-5 minutes and, with a hilly second half, the Beachy Head 9 minutes is more than justifiable!  I still think my overall time wouldn't have been as quick if I'd started out slower so I'd agree with you there.