How long is a marathon?

Never used a GPS watch in a marathon before but used my all singing and dancing garmin for London. I know GPS isn't accurate enough as a measure - especially in a marathon with tunnels and flyovers like London has so I'm glad I was using their mile markers as a guide. I got 26.8 in the end. No idea how much was down to satellite signal and how much was me not staying on the racing line. What distances did you record?


  • 26.7mi on my Polar M400 yesterday.

  • NickW2NickW2 ✭✭✭
    26.7 using strava on my iPhone
  • I use a Tomtom Runner which pretty much nails GPS tracking all the time. I used it for Brighton and recorded 26.3 miles.

    I briefly upgraded to a supposedly superior Garmin, but after 4 days returned it as it was hopeless at accurate GPS tracking compared to the Tomtom.

  • 26.33 in London just gone.
  • 26.3 for London this weekend. I was trying hard to stay by the blue line though.

  • GoldeagleGoldeagle ✭✭✭

    26.46. Seem to have visited a few offices in Canary Wharf.

  • My track is really good until Canary Wharf too. Maybe I went for a few coffeehouse visits that I forgot about.
  • Brighton 26.36
  • FreemersFreemers ✭✭✭

    27.1 in London on Sunday.  I was close to the blue line for much of it, so just shows it all goes haywire with the underpasses.  Still, does this mean I can claim to have done an ultra?

  • PhilPubPhilPub ✭✭✭

    26.47 for London, pretty standard for me.  (Garmin 220). Strava trace shows the usual blips at Canary Wharf, popped into a few offices to do some blue-sky thinking with Goldeagle.  image


    BTW, 6,220 people have Strava traces from Sunday if you want to expand your sample size.

  • Ooh - nearly snap Catalin.

    Brighton - 26.37

    Definitely some extra distance weaving around the folks who put themselves into too fast a starting corral ????
  • 26.6 for me at London - significantly further than Marigold - is that why I'm slower image Mind you it would have been less if I didn't keep having to dodge the *rse who was determined to run along the blue line no matter how many times that meant barging me out of the way or cutting me up................

    If you think you can or you think you can't you're probably right.
  • PhilPubPhilPub ✭✭✭
    Little M.iss Happy wrote (see)

    Mind you it would have been less if I didn't keep having to dodge the *rse who was determined to run along the blue line no matter how many times that meant barging me out of the way or cutting me up................

    Take consolation in the likelihood that they ran further than you.  They're probably too stupid to realise that weaving either side of a straight line sends you further than running parallel to it a few feet over to the right.  image

  • Bike ItBike It ✭✭✭

    I ran Manchester 2013 - that recorded 26.2 miles on my Garmin 310XT

  • Manchester 2016 26.30

    Broadway 2015 27.30 (went the wrong way and had to phone the RD for directions)

    Brighton 2014 26.36



  • Manchester 2015 - 26.01

    Manchester 2016 - 26.40

    Actually ran faster in 2016 strangely!!

  • Tom13Tom13 ✭✭✭

    Manchester just gone-26.39

  • MeadowerMeadower ✭✭✭

    In my nine to date, the shortest was Beachy Head 2015 in 41.58km (one of three to come in below distance according to Garmin).

    The longest was the 2016 Disney marathon at 42.94km.  This did include me running off course for character photos... the next is Berlin at 42.65km.  And it's supposed to be fast, hah!

  • Brighton 2016 26.40

    NYC 2015 26.43

    London 2015 26.78

    They seem to be getting shorter every timeimage

  • I got 27 miles bang on in London on Sunday but then I was so caught up in the emotion of it all that I forgot to switch off Garmin till I was picking up my bag - twit!  I did also do quite a bit of weaving as I was at the back of the field and when I had my rare moments of 'speed' in the latter stages in particular, there were quite a few walkers to navigate round.  It was getting depressing though - hearing the beep of my mile markers and actually knowing the real mile markers weren't even close. 

  • 26.35 at Brighton this year, with a Garmin Forerunner 210.

    Interestingly up until about 6 miles I was clocking almost dead on with each mile marker, then (and I can't quite remember which mile it was, maybe 7 or 8) I was all of a sudden 0.12 out. Seemed to get a bit back around mile 10, then lose it again around 11/12, and then gradually a tiny bit more throughout the 2nd half.

    I knew I was going to be touch and go whether I could sneak in at under 4 hours, so when I was working out target paces I went on Garmin Connect a while before the marathon and looked at lots of other peoples from the year before - most were reading about 26.4x miles, so when I was working out paces I based everything on the pace to do 26.4 in 4 hours rather than 26.2. It's only a few seconds per mile but didn't want to get it wrong! In the end I had a good day and came in at 3.58.10 for 26.35 miles so had a bit to spare even if I'd done slightly further than that.

  • ShazmoShazmo ✭✭✭

    Reemanator - I do that too, calculate my target pace for slightly over the distance. 

    London this year my Garmin measured 26.5 miles. I found it more crowded than the previous time and felt like I was weaving a lot more. 

  • 26.29 miles on my Garmin for Milton Keynes yesterday.  Garmin 620.

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