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Snoopy16

macrumors regular
Original poster
Jun 20, 2015
124
32
When I run I've been using the outdoor run feature on the watch along with starting ismooth run on my phone. The pace shown on the watch and the app are usually noticeably different. Yesterday I brought my Garmin Forerunner 15 along as well. The Garmin and the app differed by 2 seconds for a 3 mile run. The Apple watch was off my almost a minute. Periodically during my run, I'd look at each and they were never the same and often very far apart. At this point, do I need to unpair and recalibrate or can this be done without unpairing? I hate to unpair as fear I then have to set up Apple pay again. Oh, the distance is off too by about .10 of a mile.
 
When I run I've been using the outdoor run feature on the watch along with starting ismooth run on my phone. The pace shown on the watch and the app are usually noticeably different. Yesterday I brought my Garmin Forerunner 15 along as well. The Garmin and the app differed by 2 seconds for a 3 mile run. The Apple watch was off my almost a minute. Periodically during my run, I'd look at each and they were never the same and often very far apart. At this point, do I need to unpair and recalibrate or can this be done without unpairing? I hate to unpair as fear I then have to set up Apple pay again. Oh, the distance is off too by about .10 of a mile.


Make certain that Motion calibration and Distance is On in iPhone.
https://support.apple.com/en-us/HT204516
System/Privacy/Location Services/System Services/Motion Calibration and Distance/On

It takes several walks/runs with watch and iPhone together to calibrate and gets better with time. You need at least 20 min. And perhaps for each walking/ running speed.
 
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My surge differs on the same route different days, so I'm no surprised. I think the Garmin may be the most accurate but being off a few seconds or a couple of hundredths of a mile is to be expected.
 
Thanks, appreciate the info. I have done in excess of 20 runs with the watch at this point and the difference between it and Garmin on Sunday was over a minute in terms of pace which seems crazy to me. Going to see what it does today when compared to the Garmin.
 
Thanks, appreciate the info. I have done in excess of 20 runs with the watch at this point and the difference between it and Garmin on Sunday was over a minute in terms of pace which seems crazy to me. Going to see what it does today when compared to the Garmin.

Are you pausing the Apple Watch workout app during runs if you need to stop at an intersection, etc.? I know the Garmin 15 and the iSmoothrun app both have auto-pause so you don't have to worry about it. Unfortunately, the AW doesn't have auto-pause, and the only way to pause it is to force touch the screen. Kind of silly they didn't include an auto-pause feature on the AW.
 
Are you pausing the Apple Watch workout app during runs if you need to stop at an intersection, etc.? I know the Garmin 15 and the iSmoothrun app both have auto-pause so you don't have to worry about it. Unfortunately, the AW doesn't have auto-pause, and the only way to pause it is to force touch the screen. Kind of silly they didn't include an auto-pause feature on the AW.

That's a great point. I am not. Hmmm. Perhaps that's a large part of this. What is weird though is I'll look at my Garmin and it says pace is in 9 minute range and I'll look at AW and it will be a full minute different. I'd love to just rely on it during my run to get a sense of my pace. I always have my phone and am fine for relying on ismoothrun to have a reasonably accurate final pace that I can upload to Strava.
 
That's a great point. I am not. Hmmm. Perhaps that's a large part of this. What is weird though is I'll look at my Garmin and it says pace is in 9 minute range and I'll look at AW and it will be a full minute different. I'd love to just rely on it during my run to get a sense of my pace. I always have my phone and am fine for relying on ismoothrun to have a reasonably accurate final pace that I can upload to Strava.
Sorry but you can't. I have had mine since launch day and run 3 or more times a week and always with my iPhone. The :apple:Watch will drift in accuracy. Some runs it will be dead on but other times if can be off by a fair percentage. Yesterday I ran 7 miles and it was 7.03 on my Garmin 620 and 7.00 on my :apple:Watch, so near dead on. Saturday my Garmin was 10.04 and :apple:Watch 9.98. But last Thursday my Garmin 5.00 and :apple:Watch was 4.73. Last Monday my Garmin had 5.75 and :apple:Watch was only 4.84 which is a 17% difference.



It doesn't use GPS coordinates for mapping and just seems to be calibrating the accelerometer in real time.
 
Sorry but you can't. I have had mine since launch day and run 3 or more times a week and always with my iPhone. The :apple:Watch will drift in accuracy. Some runs it will be dead on but other times if can be off by a fair percentage. Yesterday I ran 7 miles and it was 7.03 on my Garmin 620 and 7.00 on my :apple:Watch, so near dead on. Saturday my Garmin was 10.04 and :apple:Watch 9.98. But last Thursday my Garmin 5.00 and :apple:Watch was 4.73. Last Monday my Garmin had 5.75 and :apple:Watch was only 4.84 which is a 17% difference.



It doesn't use GPS coordinates for mapping and just seems to be calibrating the accelerometer in real time.

Thanks Julien. I will just have to wear both as I need to be able to see an accurate pace, but also want to fill up the loops and track steps. Those discrepancies really add up on the long runs.
 
Thanks, appreciate the info. I have done in excess of 20 runs with the watch at this point and the difference between it and Garmin on Sunday was over a minute in terms of pace which seems crazy to me. Going to see what it does today when compared to the Garmin.
I run with a Garmin, and I do not use auto pause. When I first got the watch and gave it time to calibrate, it was consistently about 0.1 miles short on a 5 mile run. This translates pretty consistently to the watch reporting about 10 seconds/mile slower than my Garmin.

Since then, I have changed my cadence and stride to improve running efficiency. I am probably about 7 steps/minute faster cadence than before (pace about the same). As you might guess, the watch is now over-reporting distance by 1/4 mile or more on the same 5 mile run, and it is reporting average pace about 40 seconds too fast.

The calibration on your watch must be massively off, if you are seeing pace differences greater than a minute. You may need to force the watch to re-calibrate. That is what I need to do with mine.
 
Good thread to read. One of the main reasons I did not get the apple watch over the 920 xt. Would love to have the apple watch but really needed a upgrade from the 310 xt. I do hope they put an actual gps in the watch at some point.
 
I run with a Garmin, and I do not use auto pause. When I first got the watch and gave it time to calibrate, it was consistently about .1 miles short on a 5 mile run. This translates pretty consistently to the watch reporting about 10 seconds/mile slower than my Garmin.

Since then, I have changed my cadence and stride to improve running efficiency. I am probably about 7 steps/minute faster cadence than before (pace about the same). As you might guess, the watch is now over-reporting distance by 1/4 or more, and it is reporting average pace about 40 seconds too fast.

The calibration on your watch must be massively off, if you are seeing pace differences more than a minute. You may need to force the watch to re-calibrate. That is what I need to do with mine.

Is there a way to force it to re-calibrate other than unpairing and re-pairing? Thanks.
 
That is what I am trying to figure out now. Called Apple support yesterday, but they gave me confusing info. Calling again to clarify...
 
I run with a Garmin, and I do not use auto pause. When I first got the watch and gave it time to calibrate, it was consistently about 0.1 miles short on a 5 mile run. This translates pretty consistently to the watch reporting about 10 seconds/mile slower than my Garmin.

I think the OP was referring more to average pace then distance. Whether or not you use auto pause would have no impact on distance, but if you don't pause the AW, and the Garmin or iSmoothrun app does auto-pause then your pace will be much higher on the AW.

If you don't pause the AW, the run time continues even when you are standing still (distance stays the same). But the clock will be stopped on the Garmin or iPhone app if auto pause is enabled. Thus even though the distance for both would be close (the OP said distance was only off by .1 of a mile on the AW), the time of the run would be greater on the AW.

i.e.

AW (not paused) 42 minutes / 4.9 mile run = 8:34 pace/mile
Garmin (auto paused) 40 minutes / 5.0 mile run = 8:00 pace/mile

The AW is only going to be so accurate regardless since it is just calculating distance by stride length x steps. I think we will see all of this improve with WatchOS2 as some of the 3rd party developers (like iSmoothRun) are probably more in touch with what runners want (like auto-pause) than Apple seems to be. I know that iSmoothRun is working on a native app for the AW that I am sure will be much more feature rich and accurate than the Apple Workout app ... plus 3rd party apps can update the exercise rings in WatchOS2 ... so you won't have to run both apps.
 
Is there a way to force it to re-calibrate other than unpairing and re-pairing? Thanks.
It calibrates continually, if you let it. And it's uses the iPhone GPS to do that.

You guys made me curious. Took a walk with my Apple IPhone watch and Runmeter app on my iPhone 6, that uses GPS to map my run, with stats. Screen shots below. I made 2-3 short stops for passing cars, but otherwise walked continuously. iPhone in front pants pocket.

Looks pretty good. 1.81 vs 1.80 miles; avg pace 17'48" vs 17'53"; time is spot on, 32:14 vs 32:15. Calories are different, but I'd expect that. One is using heart rate the other not.

Asking for better than that, is too much. Perhaps your errors are in uneven or inconsistent arm swing and body motions. If you want to run without the phone you have to maintain arm swings, as that is what you are calibrating. Otherwise keep the phone with you, with the GPS motion distance calibration on.

b719f75effba445d1beb83b59cc5dcc7.jpg


44ff5d9bf35cabb02f560c151eac07ff.jpg
 
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I think the OP was referring more to average pace then distance. Whether or not you use auto pause would have no impact on distance, but if you don't pause the AW, and the Garmin or iSmoothrun app does auto-pause then your pace will be much higher on the AW.
I think we are on the same page. I was not sure whether the OP was using auto pause on his other devices or not. So, I gave the full data dump on what I am seeing without auto pause in play on any devices.

As tangential data point, I turned off auto pause on my GPS watches years ago, because they stopped a little too aggressively and produced inaccurate results. I do not run in areas with stops, so has not been an issue for me.
 
Is there a way to force it to re-calibrate other than unpairing and re-pairing? Thanks.
Well, I just got off the phone with Apple support and they confirmed that an un-pair/re-pair is the only way to calibration data. You lose Apple Pay plus minor miscellaneous things. It is kind of ridiculous, actually. Recalibrate should just be a button on either the Workout app or on the iPhone watch app. I am probably not going to mess with it.
It calibrates continually, if you let it. And it's uses the iPhone GPS to do that.
Yes, but I have no idea how long that would take. When I got the watch, I ran every time with my iPhone for about 70 miles to allow it to calibrate. Presumably, it has about 10 hours of calibration data. So, do I need to run another 70 miles to flush those old data out, or do they flush out in the minimum 20 minutes that Apple references in their calibration instructions? And, does it ever truely, fully flush out? Since I know the calibration is wrong, I would rather Apple give us a straightforward way to correct it immediately.
 
Well, I just got off the phone with Apple support and they confirmed that an un-pair/re-pair is the only way to calibration data. You lose Apple Pay plus minor miscellaneous things. It is kind of ridiculous, actually. Recalibrate should just be a button on either the Workout app or on the iPhone watch app. I am probably not going to mess with it.

Actually that is not what Apple is saying. You do lose calibration when you unpair, but calibration will be refined and change as you use it too. But you have to do it correctly as the location setting is not a default option. See Apple link above.

Here is my guess. If you always run with the GPS on AND in a Workout Watch mode, it will use the time and GPS to calculate your pace accurately. If GPS is off, or watch not present, it will use the accelerometer: and that accuracy depends on your pace somewhat, and what pace you used to calibrate. It is what it is.
 
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So my Garmin and iSmoothRun are both using auto pause. What seems so odd to me is that I look down at my right arm (Garmin) and pace is in the 9 min range. I look at other arm at Apple watch and it's way off. I am going to restart phone and watch tonight before my run and see what happens. I always run with my phone and don't plan to change that. Thanks for so much great info. I appreciate it!
 
Actually that is not what Apple is saying. You do lose calibration when you unpair, but calibration will be refined and change as you use it too.
The Apple support rep answered the specific question I asked, which was "how do I force the watch to forget its running calibration and start over." I figured that old calibration data would eventually dilute out, but I did not want to wait for that, since I knew that the current data were wrong. Plus, I have run at least 2 hours with the phone and my new cadence, but it has not materially altered its calibration.
 
So my Garmin and iSmoothRun are both using auto pause. What seems so odd to me is that I look down at my right arm (Garmin) and pace is in the 9 min range.
That probably solves it. You might try testing by turning off the auto pause on both to see how all three compare.

Also, unless you are running in something like a city with frequent forced stops, you might consider dumping auto pause. You might find that the AW is actually giving you a more accurate picture of your run than devices with auto pause.
 
I did some walks and runs. I'm concluding that AW pace calculation is too simple and shouldn't be trusted, although the time and distance measurements are precise and calibrated for me.

It seems that AW does pause, but does nothing with the data.

One example. I did a walk/run, where I paused for 4 minutes. AW and GPS Runmeter (with pause detection on) running. During the walk/run, the AW was displaying real time pace ( that reflected what I was doing), and when stopped, the pace went to --'/--" mile. The lag on the display update was obvious. The Runmeter app also showed that I was stopped.

The final numbers for miles was precise. But the Apple watch basically ignored the pause and divided total time/distance, while Runmeter subtracted out the 4 minute pause first.

So Apple has the info there, but doesn't use it. Perhaps OS 2 will be smarter.

For me, if I walk at the same calibrated pace, without pausing, it works fine. I'm mainly interested in distance.

Yes, un pairing is the only way to start over. From there it's not flushing out old data but probably averaging in data rather quickly if there is not much scatter in the data. But given the simplistic algorithm used above, who knows..

I think the hardware is fine, but Apple needs to bump up its software and how it uses the data at hand. Seems good for distance, instant pace and heart rate perhaps for calories burned. But maybe not for average pace with stops as displayed in the activity app., or uneven cadence too?

Seems to be what you guys are finding.
 
If anyone is interested, the Runmeter Elite edition has a complimentary AW app that allows control of the iPhone app from the wrist. The watch real time displays are excellent, with pace, miles, etc. uses pause, if desired, and of course the GPS in the phone for measurements and mapping. It's just a watch remote, but you will get a Move credit on your watch.

Basically gives you an accurate pace.
 
I would hang up the shoes if I ran a 17 min mile. No speed demon but not a extra on the Walking Dead either. This is what the AW told me I ran the other day.

Full disclosure running the public beta 2 on the iPhone so wondering if this is the issue.
image.png
 
I would hang up the shoes if I ran a 17 min mile. No speed demon but not a extra on the Walking Dead either. This is what the AW told me I ran the other day.

Full disclosure running the public beta 2 on the iPhone so wondering if this is the issue. View attachment 573359

Did you stop during the first mile and not pause the run?
 
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