2013 Virgin London Marathon Splits

I’m not a fan of marathons as part of the build up to an Ironman, but I still had a few of my athletes racing at the Virgin London Marathon. Yesterday evening I checked their results to see how they’d got on and once again found myself frustrated with a results system that offered limited access to the results data – I want to be able to examine the full set of data and place my athletes in context. Unable to get what I wanted I put together a new script to fetch all the finisher results from the London Marathon results pages and compile it into a database.

Average Pace During the 2013 Virgin London Marathon By Finishing Hour

Last year I briefly compared the pacing of stand-alone marathons with Ironman marathons to see how they differed. One observation at the time, which can be seen again in the chart above, is that on average there really isn’t much difference in pacing strategy regardless of finishing time: most go out fast and finish slower than they started, this is most marked among the slower runners. The classic negative split is not the average. Interestingly, assuming timing mat placement is precise, the halfway point provides a psychological boost with many running the kilometre that leads to the half marathon split faster than the previous 5K.

I haven’t had time to examine the results further, with 35,000 finishers this is a much larger dataset than I usually work with. Too large for Google Drive, so instead of the usual spreadsheet I’ve uploaded an unwieldy (12MB) zip file containing the full data in Excel format. You can download the amateur splits from the Virgin London Marathon here (click File and select Download to save a copy). I’ll take a closer look at the results later this week.

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  • James Hartwright

    Can you adjust the scale so that the 20-21.1km is in proportion with with otherwise 5K splits? I think that this km was marginally downhill and it was also one of the busiest points for spectators which would give many people, particularly slower runners a boost.

  • Christof Schwiening

    I have taken the liberty of using your harvest of data to calculate each runner’s placing at each time check. The Excel spreadsheet allows two runners progression through the field to be compared. If you have wondered just how many runners you past, or past you then the result is here……for some the graphs look ugly. I have selected two friends in this sheet who used different strategies but finished very close.

  • James – I’ll do a properly scaled version next time I post about the results set.

    Christof – that’s great, like the functionality. I may have to borrow that idea for some of the other, smaller, results sets I’ve worked with.