How do you measure yours?

dna_leri

I recently tried to measure a 1 mile stretch of road so I could do the key workouts as described in this thread. I first used mapmyrun (manually mapping the points using satellite picture, not just following the map) and then used sports-tracker on my phone when I did the session. I found a difference of about 100m between the two, which is significant when trying to time a 1 or 2 mile trial.

In this case using the track is not an option as I want to simulate race conditions.

I do not have a garmin, would it more more accurate than the GPS on a phone?

I know I could get a trundle wheel and measure it out, which is a lot cheaper than a garmin, but a bit of a pain.

How do you measure yours?

Whitehawk

Well as long as you keep useing the same thing(prog) its ok as the dis. error dose not change! i use mapmyrun btw

RayCun

dna_leri wrote: »

I do not have a garmin, would it more more accurate than the GPS on a phone?

The garmins are usually accurate to within 2-3%. I'd guess phones will vary a lot.

shels4ever

dna_leri wrote: »

I recently tried to measure a 1 mile stretch of road so I could do the key workouts as described in this thread. I first used mapmyrun (manually mapping the points using satellite picture, not just following the map) and then used sports-tracker on my phone when I did the session. I found a difference of about 100m between the two, which is significant when trying to time a 1 or 2 mile trial.

In this case using the track is not an option as I want to simulate race conditions.

I do not have a garmin, would it more more accurate than the GPS on a phone?

I know I could get a trundle wheel and measure it out, which is a lot cheaper than a garmin, but a bit of a pain.

How do you measure yours?

If I were you would just pick one or the point and stick to it(maybe the longer one), For the sessions if your doing .95 or 1 mile wouldnt make a huge difference, just keep a track of your times.
Then at some point try to get access to a track and do the same session then you would have a good idea.

TheRoadRunner

dna_leri wrote: »

I first used mapmyrun (manually mapping the points using satellite picture, not just following the map) and then used sports-tracker on my phone when I did the session. I found a difference of about 100m between the two, which is significant when trying to time a 1 or 2 mile trial.

I've found GPS on my phone is as accurate as my Garmin. I'd go with the phone.

dna_leri

I get the bit about just picking a route and sticking to it to see the improvements and where possible I would do that.

Last week I was doing the final 3x2M workout before next week's 10K and had to do it close to home due to time constraints so the usual route was not possible.

Good to know the Garmin is no better than a phone GPS so I don't go wasting my money.

2-3% is significant in a 10K though - its the difference between a great time at 38:59 and failure at 40:09 !

I guess it a trundle wheel then or just stop obsessing about accuracy and go out and run !

stmochtas

Years back I remember using a car to measure out a mile. Accuracy would be down to the car's odometer but it might be a useful cross check.

Krusty_Clown

In my humble opinion, in order of accuracy (least to most):
Phone with GPS
Mapmyrun
Car Odometer
Garmin Forerunner
Car or other dedicated GPS device
Commercial/Industrial GPS receiver
Trundle Wheel
Jones Counter

So if you want to measure a specific distance with some degree of accuracy, then borrow a car-based GPS and walk the route (with road lock turned off).

If I want to measure a route, I'll usually use Garmin mapsource with OpenStreetMaps. The results are only as good as the mapping and may not give you the kind of accuracy you are looking for, but for most purposes, the results are fine.

dna_leri

Krusty_Clown wrote: »

In my humble opinion, in order of accuracy (least to most):
Phone with GPS
Mapmyrun
Car Odometer
Garmin Forerunner
Car or other dedicated GPS device
Commercial/Industrial GPS receiver
Trundle Wheel
Jones Counter

So if you want to measure a specific distance with some degree of accuracy, then borrow a car-based GPS and walk the route (with road lock turned off).

If I want to measure a route, I'll usually use Garmin mapsource with OpenStreetMaps. The results are only as good as the mapping and may not give you the kind of accuracy you are looking for, but for most purposes, the results are fine.

I had not thought of the car-based GPS, - good idea.

As usual the definitive word on the subject of GPS goes to Mr KC.

aero2k

A bicycle computer should be +/- 1% accuracy if it's calibrated properly. They count wheel revs so the longer the distance you're measuring the more accurate the result.

You can get them in Lidl/Aldi for €15 or so.

Krusty_Clown

aero2k wrote: »

A bicycle computer should be +/- 1% accuracy if it's calibrated properly. They count wheel revs so the longer the distance you're measuring the more accurate the result.

You can get them in Lidl/Aldi for €15 or so.

Depending on your tyre pressure, right?

aero2k

Krusty_Clown wrote: »

Depending on your tyre pressure, right?

11 bar and me at 66kg => very accurate!:pac:

I did say properly calibrated which implies the person who's going to ride the bike over the course to be measured should be on it when it's rolled along a measured straight line. I've only ever measured one revolution but then I'm happy with an approximation.