Park run question 😊

[Buddy34]

Is it just me or does anyone else's parkrun fall a tiny bit short of 5k.

The last few were 4.86,, 4.84 .

Or is it my garmin that's the problem.

Not a big deal just a question 😊😊

[FatterPenguin Graduate10]

Mine feels like it's 10 miles too long....

seriously though I believe mine is spot on, though runner friends of mine have said others are a bit short too.

[Buddy34 Graduate10 in reply to FatterPenguin]

😂😂.

[Mummycav Administrator Graduate10 in reply to FatterPenguin]

😂😂😂😂

[Annieapple Administrator in reply to FatterPenguin]

🤣🤣🤣

[RunningChocoholic Graduate10 in reply to FatterPenguin]

😂😂😂👍🏻

[AlMorr Ambassador Graduate10]

Good morning Buddy34, there have been a few queries regarding parkrun distances, I always go by the official one, however, some runners have said that their own time or distance isn't exactly the same as the one at the parkrun, next Monday I'll be at Drumpellier and just walk around it with Mapmawalk and see if that is the same as the official one on a Saturday.

[roseabi]

It's unlikely that either your watch OR your parkrun are 100% accurate. GPS is prone to interference, and watch technology has its limitations. And, while the parkrun distance will have been measured carefully at first, I imagine that inconsistencies of cones and/or marshal positioning will have crept in over time 😊😊😊

[sTrongFuse Graduate10]

Parkruns, like most organised runs will have a measured distance of 5k for the "optimum" race line. The problem is that almost none of us ever run that line; we cut corners, dodge puddles, get out of the way other runners, etc. Then, as roseabi says, there will be some inconsistencies due to the marshal/cone position and the inaccuracies of phone/wrist worn GPS (my local parkrun gets "longer" in winter because there is less signal interference from leaves on trees. There are, however, some that are definitely short. Vogrie has a reputation for being about 300m shorter than it should be and given that everybody comments on it being off by roughly the same amount, I suspect there has to be something in it.

[RunaroundSue Graduate10 in reply to sTrongFuse]

We almost got to Vogrie in June but mistimed the weekends of our trip so we went to Druridge Bay followed by Ellon.

It's still on our list as a stopping off point when we visit friends near Aberdeen so maybe next year.

Interesting to hear that it might be a bit short, but that doesn't bother me. Unless of course it gives me a chance of a pb

[sTrongFuse Graduate10 in reply to RunaroundSue]

I have two very close and pretty much equidistant to me, Vogrie (which is quite hilly in places) and Meadowmill (which two small climbs aside, is like a snooker table). Guess which one I've run quicker?

It's a bit of a running (no pun intended) joke that if I want a 5k PB I go to Meadowmill and if I want a Parkrun PB I go to Vogrie.

Both are good, but if you're "touristing" I'd choose Vogrie as it's a much nicer setting in the grounds of what used to be a stately home, where as Meadowmill is a couple of laps of some local authority playing fields. Both have very good cafes for after, but Vogrie still tops the two.

[RunaroundSue Graduate10 in reply to sTrongFuse]

Thanks, useful information. Vogrie does sound more interesting. Plus it's a V for the alphabet challenge

Maybe next year. We want to go back to Dunbar and North Berwick anyway.

[sTrongFuse Graduate10 in reply to RunaroundSue]

There's also Lochend Woods at Dunbar. You also Have the Cramond (Edinburgh), Portobello parkruns nearby as well as one that has just started at Oriam (Heriot-Watt University) on the west side of Edinburgh.

[Buddy34 Graduate10 in reply to sTrongFuse]

The full list of Scottish parkruns are on YouTube. There's a guy who's ran every one apart from one which I think he's doing this Saturday . His name is Douglas Mason

[sTrongFuse Graduate10 in reply to Buddy34]

I believe he achieved (what is now impossible because there's too many) the feat of running every Scottish one in a single year.

[RunaroundSue Graduate10 in reply to sTrongFuse]

I know, we have done the one at Cramond. I saw all the others but we camped at Dunbar then North Berwick during the week, so couldn't fit in a parkrun. Another time we will do so.

[ArthurJG Graduate10 in reply to sTrongFuse]

The fact that Vogrie consistently measures short does not necessarily mean it’s short. If there is a corner or curved section that is inaccessible to GPS signals then everyone’s watch will go out of signal, everyone’s curve will be misinterpreted as a straight line and everyone will have an underestimated distance. There is a reason the athletics authorities don’t use GPS to measure courses: if it were reliable it’d be easier and cheaper than what they actually do. Parkrun isn’t as fussy as official race bodies in the way it measures courses so it won’t always be exactly 5km but I’d be very surprised if a course was actually as much as 300m short on a consistent basis. Remember the GPS signal comes from 24000 km above you. Just because it’s on a computer doesn’t mean it’s accurate.

[Katnap Graduate10]

Stop cutting the corners? 😲

Seriously though, our local pr often goes shy of 5k and running wide helps

[Buddy34 Graduate10 in reply to Katnap]

Oh so it's my fault 😂😂

[Mummycav Administrator Graduate10 in reply to Buddy34]

😂😂

[Katnap Graduate10 in reply to Buddy34]

And GPS can be a bit out on some days...

[cheekychipmunks Graduate10 in reply to Katnap]

Yours came up as 4.96k on my Garmin last Saturday Katnap, but I was on the inside line with Flossie at the beginning. 🏃‍♀️🐕

[Katnap Graduate10 in reply to cheekychipmunks]

I got 4.98 km ...

Tailchaser got 5k

[Sandie1961 Graduate10 in reply to Katnap]

I was 5.08. Blooming good job too as it was the fastest 5k I’ve ever run. My last PB at Market Rasen only recorded 4.98 so didn’t register!

[Katnap Graduate10 in reply to Sandie1961]

Hooray and grrr....

[iain-strachan Graduate10]

Yes, on my Garmin, the Abingdon Parkrun comes out at 4.93 km. I am not sure of what accuracy GPS is supposed to be but I'm fairly sure 10 meters is about right so it could be anywhere between 4.92 and 4.94.

Of course the length will also depend on where you start - but I don't start anywhere near the front so if anything that would add 10-20 m to the overall distance.

[iain-strachan Graduate10 in reply to iain-strachan]

Well I just did an experiment and traced out the course using onthegomap.com following the plotted course on the Abingdon Parkrun website and the distance comes out at 5.05 km. The only thing I can think of is that we don't run the actual course. At the start a lot of people go to the left of a bunch of trees rather than on the tow path (where it can get bottlenecked) and possibly that accounts for the difference. Though I would not have thought it made that much difference. Or possibly we all start a little ahead of where the official start point is.

[Chris141 Graduate10]

Yes we have had similar issues at Harlow. After extensive research it appears that the problem lays with smart watches, running apps etc and not with the actual measurement of the course. My Run Keeper app sometimes shows 5K sometime shows a little short but regards it as a 5K.

[iain-strachan Graduate10]

Found the problem. It seems to be a GPS error - the Garmin GPS has cut off the corners. Here's a link to the Strava trace for part of the run dropbox.com/s/orbwvuarw8dwo...

The actual run goes on the yellow dotted pathway, but the GPS has cut this off and rounded the corners. I'm pretty sure that would have accounted for the discrepancy. Nor is it a random error because there are two laps.

It is possible that a path has been worn across the field by many runners that does take the course shown rather than the yellow dotted path - but that is the official course, as you can see here: google.com/maps/d/viewer?mi...

[iain-strachan Graduate10 in reply to iain-strachan]

It's not just the Garmin - My son did the same Parkrun and having looked a his Strava it shows the length as 4.88 km, and the same corner cutting-off (and he doesn't use a Garmin - he has an Apple Watch). I wonder if the path marked on Google Maps is incorrect?

[UnfitNoMore Graduate10 in reply to iain-strachan]

It’s a weakness in the way watches, including the Apple Watch, use the GPSr... the Apple Watch is much more accurate when connected to an iPhone. Not sure if the watch with phone capabilities suffers as much.

[iain-strachan Graduate10 in reply to UnfitNoMore]

But my watch is connected to the smartphone (Samsung Galaxy). Before I got the watch I noticed that the GPS on the phone was appallingly inaccurate - it had me running straight through a block of houses like a ghost! An IT expert at work reckoned I ought to get a running watch as it would be more accurate, and by and large it is. But occasionally you get a large wobbly!

But several of my friends have noticed that the Abingdon Parkrun comes out at less than 5km - different watches, same result. It's quite a puzzle.

[UnfitNoMore Graduate10 in reply to iain-strachan]

It may be connected but it won’t be using the phone’s GPS. I haven’t used a Samsung phone, so I don’t know about their accuracy, I believe they have a different family of GPSr to the iPhones... which is shocking as they’re no doubt made next to each other!

The watches don’t use GPS constantly like the hiking devices do, so they will get a position every few seconds... so when you turn a 90 degree left, if you don’t apex that corner as it gets a position, it will assume a straight line from the last time it got a position. They’re pretty accurate in straight lines... turning a 180 is probably the worst thing you could do to it of course. Your wrist based device should therefore lose a few yards at virtually every corner.

Some watches let you shorten the time between position fixes, but this doesn’t help the accuracy much as it then becomes more susceptible to the error in location.

[iain-strachan Graduate10 in reply to UnfitNoMore]

I do understand about cutting corners off especially if it only samples relatively infrequently, but in the Strava plot of my Parkrun dropbox.com/s/orbwvuarw8dwo.... you will see that not only does it cut off the corners but it never gets near the actual route when it's straight (mostly on the yellow line on the graph). It does the same thing twice as there are two laps, and my son's one on his Apple Watch + iPhone does exactly the same. For the "true" route which is 5 km exactly, see google.com/maps/d/u/0/viewe...

[UnfitNoMore Graduate10 in reply to iain-strachan]

That Strava plot is strange... trying to fathom that still, it’s not what I’d expect to be seeing... keeping to the path 100% would be unusual, but to never be on it at all is crazy.

I’ve yet to have my watch record any parkrun as 3.11 miles, though one was close with 3.06, all the rest have been under 3

[sTrongFuse Graduate10 in reply to UnfitNoMore]

GPS error is certainly a factor, but probably only 10-20m over the piece. At Vogrie, pretty much everyone reports it as being around 250-300m short so I suspect there has been an error (probably in the position of the starting point) allowed to creep in.

I don't mind though, it is a lovely spot about 20 miles south east of Edinburgh and pretty much right on my doorstep, and I can never sing the praises of the cafe too highly.

[Grannyhugs Graduate10]

I did my 1st 5k race 3 days after graduation, was so nervous as I'd never run with anyone before and hadnt reached 5k in 30mins - huh, turns out the course was 4.8, could have saved a whole lot of worry! I guess it's to do with how many twiddly bits they'd have to add in to get that extra part km.

[Maddee_6333 Graduate10]

Mine normally does. I suppose it depends on what line you take. Maybe start at the back and hit start on your tracker before the start line.

[Zebadee1]

I normally start at the back and it always shows slightly over 5km..My official time is also always few seconds more - because I start at the back. Thankfully I'm not competative so don't mind (although I might try to sneak closer to the front next time I make it to the Parkrun 😉)

[JaoJao Graduate10]

My home park run is exactly 5K. Another parkrun close to me I measured 5.3k 👀

[Tasha99 Graduate10]

Some are short. My local is 5.1 😕

[UnfitNoMore Graduate10]

On my “home” parkrun the Garmin regularly measures it at 2.85 to 2.95 miles... my phone (Nike run club app, but this should be irrelevant as the hardware is doing the work) measures it between 3.09 and 3.15 miles.

So, it’s possible that the course is slightly short, but not too likely to be out my more than a few metres... they were originally measured, and when the council changed a path on my home one the event director had it remeasured, and added a 12m section in to allow for the changes. Not sure all event directors do this, and I’m pretty sure that they’re not going to be 150m out unless they really mess up putting the signs out!

Garmin support told me my phone will always be the more accurate device of the two.

[Bike_and_Run Graduate10]

Me and my mate both use Strava to track our runs (doesn't everyone?) We run the same parkrun together and yet my distance usually tracks at 4.6km while his often tracks at 5.3km.

Our times aren't too different from the official Parkrun clock but when we compare our Stravas, my mate always shows a faster pace, even though I always beat him.

I put it down to GPS errors and expect all three of us (my phone, his phone, Parkrun distance) to all be wrong.

But who cares. It's a ball park figure and shows were improving or at least just keeping active.

[Dexy5 Graduate10]

Ours comes to 5.1 so at least garmin recognises the PBs! I have noticed that when garmin downloads to Strava it ends up as 5k.???

If I come across one that is less , I try to keep moving until it’s 5k. I guess it could be a bit of GPS and a bit of running the shorter route round bends etc. Course lengths are usually based on the centre of the path.

[Getfitok]

I’ve only done parkrun once but my Garmin said it was short. I ran back to the car afterwards so that my 5k registered on my watch 😂

[RunaroundSue Graduate10 in reply to Getfitok]

I always forget to stop my watch anyway, so it is usually over 5k by the time I remember

[RunaroundSue Graduate10]

Usually mine is about 4.96, although other people get different distances. We think it is shorter in summer than winter because there is a railway embankment along part of it and the leafy trees block Garmin we think. Also, part of the path has definitely migrated further into the meadow since the parkruns started.

My husband's garmin regularly tells him that he ran in the river rather than alongside.

But last Saturday they had to change the route slightly because the river drop had dropped! making the path unsafe. Several people commented that the parkrun was now 5k.

[UpTheStanley Graduate10]

I've got a Forerunner 35 which often does strange things. My trace for the Bristol 10k showed me crossing and recrossing the Avon Gorge where there aren't bridges, and the elevation trace showed me up on the Clifton Suspension Bridge when I ran underneath it. My home parkrun regularly comes up at 5.03. My trace usually reflects where I go pretty accurately, but Dexy5 's almost always shows her outward leg running down the middle of the road instead of along the prom. And there's a place on Hayling Island where the instantaneous pace readout always shows over 9'00"/k, regardless of whether I'm pushing around 5'30" or cruising at 7'30". But I generally trust it with regard to total distance.

For parkrun, I always start my watch when I cross the start line, and when I'm touring I record watch time, watch distance, official parkrun time, and time to 5k if the watch thinks I went further.

With regard to PBs, as far as I'm concerned I've run 8 different parkruns, so I've got 8 PBs, ranging from 22'59" (Southsea, 4 years ago ) to 27'15" (Hyndburn). If I ever run Whinlatter, I'm certainly not going to be using my Southsea PB as any sort of target .