RunDisney accuracy

[adjensen]

I really hesitate to post this, but it's a general question based on my observations.

For the past three months or so, I have been training with the Nike+ Run Club application on my iPhone -- I wanted to make sure that I stayed within the 16 minute mile cut off.

I used the app on a couple of runs, including a 15K here in Port Orange, FL, and it seemed pretty accurate.

Then came the Wine and Dine Two Course Challenge 10K on November 4. I clicked the "Start" button in the Nike app as I crossed the starting line. The app announced I was at the one mile point about 90 feet away from the one mile marker. That difference continued throughout the course -- the distance increased and I was always "ahead" on my run, and when all was said and done, the app claimed that I ran 6.48 miles, not 6.2 (see attached picture) My pace, per the app, was 14'09, Disney reported it at over 15 minutes.

For the half marathon, the second day, it was even worse -- every Nike milepost was further and further from the Disney sign, to the point that for the 11th, 12th and 13th mile, the Disney sign wasn't even in sight and it took minutes to finally catch up to it. And, once again, my phone app reported my pace at less than 15 minutes per mile, Disney showed me in at 15:33/mile

After that, I figured that there was a problem with the Nike+ Run Club app, because I figured that Disney would make every effort to be accurate, and they most certainly wouldn't make their courses LONGER than they should be, because they want people out of the parks, asap. I registered a complaint with Nike.

Fast forward to the next weekend, and I'm running a 5K in Gainesville. I click the "Start" button as I cross the line and, as I cross the finish line, the Nike app tells me that I'm done with my 5K.

So, pretty good accuracy, out of Disney. Totally out of accuracy, on two RunDisney runs.

Do you have any data to add to this, either Nike being right and Disney being wrong, or the other way around? I'd really like to know, and I'm sure that Nike would like to know, and RunDisney would like to know.

One would think that there is a standard mile, and that both Nike and Disney use that standard mile, but my personal experience is that this isn't the case. Who's right?

 

[rteetz]

As for race distance with Disney your mileage will more often than not be more than the course distance. For the WDW Marathon this past year I ran 27 miles not 26.2 but that is because I was weaving, stopping for characters, bathroom stops, etc. all those small distance add up. With a smaller local race you will more likely be closer to the actual race distance because you won’t have as much extra distance added in like you have with Disney.

 

[bumbershoot]

Unless you’re one of the winners and know how to run the course perfectly, you’re weaving and moving around people and not running the course efficiently. That’s adding distance. And it’s not the fault of the course.

 

[jmasgat]

Disney courses are USATF certified for distance. FYI, here's the W&D half course certification map.

http://www.usatf.org/events/courses/maps/showMap.asp?courseID=FL17050TY

A runner with a GPS device will rarely run the exact distance for the reasons others have given. Large races with lots of people--the tendency for a runner to be off is greater.

It's not an unreasonable observation, though. So don't feel hesitant to ask.

 

[Wendy98]

Unless you’re one of the winners and know how to run the course perfectly, you’re weaving and moving around people and not running the course efficiently. That’s adding distance. And it’s not the fault of the course.

This.

I have run many, many races in my lifetime. Often, I am towards the front. I make every effort to run the tangents and still fail. I think the closest I came in marathon was 26.38, usually it is a good .5+ mile over.

 

[cburnett11]

Here's a link describing the Shortest Possible Route...

http://www.usatf.org/Products-/-Ser...dures-Manual/The-Shortest-Possible-Route.aspx

 

[camaker]

Here's another link that has a great explanation of both course certification and why the GPS distance is never in complete agreement with the certified distance. The differences that you'll see due to weaving can also be worse at Disney races because of the crowding. There are far more runners to weave around and prevent you from running the tangents than at the vast majority of local races.

https://www.dcrainmaker.com/2009/03/racing-line-understanding-how-courses.html

 

[IamTrike]

I went back to check my Garmin data for marathon weekend 2017 and it show's i ran 29 miles fort the marathon and my half distance was way off. I must have forgotten to stop it during the marathon. I pretty much agree with everyone else. The more crowded a course and the more turns on a course the harder it is to run the actual course distance. Marine Corps marathon was really bad for this for me.

 

[bumbershoot]

The differences that you'll see due to weaving can also be worse at Disney races because of the crowding.

Yep. So crowded.

 

[DVCFan1994]

I agree with others, that GPS is not perfect and unless you are a incredibly precise, you are always going to go over the mileage on a certified course.

But I wanted to add I have had a lot of issues with Nike+ accuracy. It is always over for me. I have had three GPS watches in the time I have also used Nike+, done runs with others and Nike is usually off by .05 per mile - up to .1 per mile by my estimation. I use it for audio cues only, for pace, time and distance. I liked if I wanted to go for 4 miles I could enter that and it would tell me to turn around at 2 miles, without me having to look at anything. But, whenever I did that, I added .05 to every mile to make sure I'd cover the whole distance. So I'd say 4.2 if I actually wanted 4. I don't use it during races often to save phone battery, but one I did, the 10k at Disney Avengers in 2015 it was off by over a mile. I ended at 7.4 on a certified 6.2 course. There was definitely a lot of weaving and diversions from the route for pictures, but that is still a 1.2 mile difference. I'm not sure if its where I run which has a lot of tree cover, or an issue with the phones I've used it on, but while no GPS is perfect, I have had more issues with Nike Plus than any other app I have used.

All that said, it wasn't a huge deal to me obviously, I continued to use it for 2 over two years, because I like some of the features. But I did have to remember, if it was telling me a certain pace or distance I was probably off by a little. I was sick of constantly looking at my watch so I figured audio feedback at regular intervals would help me get out of that habit. It was good for that, so I kept using it. I'm not fast or training to keep exact paces, so the 10 seconds a mile it might have been off was not a deal breaker for me. I knew the distance was a little off and had a work around for that.

 

[adjensen]

Thanks for the responses, I think that explains it, although I'm surprised that the Nike+ app is exact enough to track the distance side to side, as opposed to moving forward -- one of my complaints with it when I am training is that the mileage tracking is kind of choppy, either hampered by trees or just checking less frequently, because it will sometimes stall on a distance and then jump ahead a couple hundredths of a mile.

 

[Ariel484]

But I wanted to add I have had a lot of issues with Nike+ accuracy. It is always over for me.

I was gonna say the same thing - I think of Garmin as being the gold standard for accuracy, not Nike+.

 

[camaker]

But I wanted to add I have had a lot of issues with Nike+ accuracy. It is always over for me. I have had three GPS watches in the time I have also used Nike+, done runs with others and Nike is usually off by .05 per mile - up to .1 per mile by my estimation. .

I was gonna say the same thing - I think of Garmin as being the gold standard for accuracy, not Nike+.

I've seen some questions about Nike + app accuracy, as well. I ran a half marathon weekend before last and came up with 12.95 miles on my Garmin. A course measuring short is a huge red flag for me. In polling a number of other people, most of the Garmin results for the course fell in the 12.9-13.0 range. Only one person that I heard from came up with a distance over 13.1 and that was 13.16 miles measured by Nike +.

 

[roxymama]

Generally my 5k final distances are closer to the true 3.1 than my longer races are to their actual distances, because with those longer races you just have more miles to get more and more "off" in terms of running the most efficient route. More water table stops/more character stops for disney, etc. so I would be hesitant to compare a 5k to a half when looking at accuracy.
When I'm trying to hit a goal or PR I tend to calculate extra distance into my race to see what pace I'd have to hit just in case I run over the actual distance (and I usually do.)

 

[sunshine girl]

I think it's also easy to run long on Disney races due to the many wide roadways, plus the winding through the parks ... trying to "run the tangents" makes a big difference at Disney. In my experience, at least.

It's impossible, though - there are just too many runners! I'm not one to be obnoxious and cut off crowds of people just to run the shortest distance. But I often notice I'm waaay far off from the the technically "shortest" route at Disney. (I pay attention to the tangents because it entertains me while I run. )

 

[roxymama]

Before I ever got into running I sort of knew about tangents because the city of Chicago has a dashed blue line on many of the major streets around the city. I finally asked my husband what the heck they were and he told me that the Chicago marathon paints it as the perfect route to run. The lines fade over time but get refreshed closer to marathon day. I kind of pay attention to them more now that I run. Since I've never actually run that race I have no idea how easy it would be to stick to it in the throng of people. But it's a cool idea that they do that.

 

[Anisum]

I think just about everyone here has covered the reasons why it may seem long. I will say that runDisney isn't infallible though. There's a great post that @Ariel484 shared a while back that explains the course certification process from someone who certified some of runDisney on the West Coast events and even talks about how one course was slightly long. You can find it here. He explains that race courses certified accurate can only be 0.1% longer than the advertised distance. That being said they can't be shorter than the distance specified. The longer the race the more you weave and the more your distance may seem off. Princess Half 2016 had me at 14.2 mi. I will say that wasn't with my Garmin but instead RunKeeper which I find isn't quite as accurate.

 

[bumbershoot]

Before I ever got into running I sort of knew about tangents because the city of Chicago has a dashed blue line on many of the major streets around the city. I finally asked my husband what the heck they were and he told me that the Chicago marathon paints it as the perfect route to run. The lines fade over time but get refreshed closer to marathon day. I kind of pay attention to them more now that I run. Since I've never actually run that race I have no idea how easy it would be to stick to it in the throng of people. But it's a cool idea that they do that.

That’s really cool!

 

[IamTrike]

Before I ever got into running I sort of knew about tangents because the city of Chicago has a dashed blue line on many of the major streets around the city. I finally asked my husband what the heck they were and he told me that the Chicago marathon paints it as the perfect route to run. The lines fade over time but get refreshed closer to marathon day. I kind of pay attention to them more now that I run. Since I've never actually run that race I have no idea how easy it would be to stick to it in the throng of people. But it's a cool idea that they do that.

NY has the same blue line for the NY marathon. For Chicago I was in the middle of the pack and for NY I was in the back of the pack. I didn't have to struggle that much to stay close to it.

 

[BuckeyeBama]

I think just about everyone here has covered the reasons why it may seem long. I will say that runDisney isn't infallible though. There's a great post that @Ariel484 shared a while back that explains the course certification process from someone who certified some of runDisney on the West Coast events and even talks about how one course was slightly long. You can find it here. He explains that race courses certified accurate can only be 0.1% longer than the advertised distance. That being said they can't be shorter than the distance specified. The longer the race the more you weave and the more your distance may seem off. Princess Half 2016 had me at 14.2 mi. I will say that wasn't with my Garmin but instead RunKeeper which I find isn't quite as accurate.

0.1% of a marathon is .026 miles (140 feet) over the entire course. The poor tangents and crowds can add that for every mile.