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GoldenPRGuy

macrumors newbie
Original poster
Sep 10, 2009
23
1
Hello All,

Let me preface this post by saying I have already done a considerable amount of research on this topic and have yet to get a logical answer to my question. In hopes that someone will be able to assist, I have tried to make this post as concise as possible by breaking my thoughts into the following sections: background, calibration methods, and where I see a flaw in the Apple/Nike logic. I look forward to any and all constructive input!

Background:

I purchased a 32GB iPhone 3GS on the day it was released this past June. On August 1st I bought the Nike+ sensor and a pouch for my New Balance running shoes and went for a run the next day. At the time I really wasn't thinking about it in detail, but selected calibration, chose a 3 miles distance, and went for a run. At the end of my run when the phone registered 3 miles, I ended the workout and my phone showed it was calibrated. Over the past several months I have wracked up about 350 miles. From time to time I though it was a bit odd that runs along the same route over the same amount of time showed slightly different recorded distances and pace, but I assumed it was a slight lack of precision on the part of Nike and Apple. This past Saturday, I set out for a 8 mile run, and was disappointed when I found that almost 1.6 miles into my run, the app had only recorded 1 mile. By the end of my 8.55 mile run which I confirmed with GMAP pedometer and later with my car's odometer, my iPhone Nike+ app had only recorded a 6.45 mile run, and informed me that my pace was around 12:35/mile (much slower than my avg running pace of 8:30-9:00 min miles depending on distance and how much I drank the night before. This was clearly the worst of all previous inaccuracies - off by 2 miles! At first I thought my sensor battery was going, but Nike/Apple say you get 1000 hours of use, and I had only wracked up a cumulative 55 hours. Then I thought my phone needed a re-boot, but as I was near the Apple store I popped in for a chat with a Genius. Now I know better than to think I am going to find any runners at the Apple store, but after a logical discussion with the guy we agreed it could only be 3 things - the sensor, the phone's Nike+ receiver, or the app. So, he replaced the sensor for me. The next day I went out for another run, and mid run my iPhone (for the first time ever) completely locked up. Not one of those hard-resettable lockups, I mean DEAD, never to come back to life. I went back to the Apple store, and 10 minutes later was given a new iPhone by another genius. Now I am sure we can all agree, we have addressed software corruption, iphone hardware and the sensor. The next day I ran again. Everything started off great, the "one mile complete" prompt came up at the point that I know to be 1 mile (give or take a few strides), but by mile 3, 4 and 5+ I could tell the accuracy had really slipped. At the end of my 6.45 mile run, the phone only showed 5.6 miles ... better than the other day, but still not accurate. During this few days I've described above I had been communicating my problem with a Nike+ tech support rep. He told me that the inaccuracy was because I did not have the chip in my shoe and that a pouch was unreliable. Not a bad way to sell Nike shoes, but his logic about recording every strike through the shoe's design made a little sense. I was willing to accept this somewhat, but admittedly it seemed odd after 350 miles of pretty accurate runs. Anyway, not thinking, I set out to calibrate my iPhone again. On the iPhone you can select Calibrate, then Run, and then choose the recommended 400 meters or set a custom distance greater than 400m. I selected 400m and took off. As I ran, I waited and listened for a prompt from the phone: "300 meters to go, 200, calibraraton complete, etc." It never came! When I finally looked at my phone I had gone 3/4 of a mile. This is when I started to really think about what was happening and it hit me ... WHAT THE HELL IS THE POINT??

Documented Calibration Methods:

According to the Nike+/iPhone 3GS FAQs on both the Apple and Nike site, to calibrate the phone you select Calibration and then choose Run or Walk. If you choose Run, you are then asked to choose the distance to calibrate. The choices are 400 Meters or Custom Distance, which allows you select a distance to run. You then begin your run and end it, APPARENTLY, when the phone tells you that you have reached the distance. As I stated above it does not tell you, you need to look at the screen and determine if you've gone that far, and then you end the workout ... and viola, you're iPhone is calibrated.
On the iPod Nano, selecting calibration is done in similar way. The difference with the Nano is that you are required to determine on your own a location that will allow you to run a certain distance and then run it. When you have completed the distance (pre-determined to be X) you look at what your Nano has recorded (Y) which might be more or less than X and you dial the Y distance up or down to equal X. This process correct the Nano's readings and calibrates it.

The Flaw in Nike/Apple Logic with regard to the iPhone 3GS:

From the research I have done online and talking to techs, at no point does the Nike+ app use the GPS built in to the 3GS. The iPhone/Nike+ system measure distance by foot strikes, which determine pace. The phone uses pace and time to determine distance. This is why the Nike+/3GS works on a treadmill even though you are not going anywhere. Fine! But when it comes to calibration, the logic of it all goes to hell. In order to calibrate the PACE, you need the element of time and distance. Time is of course being measured, but without GPS or the ability to correctly dial in a distance, how is the pace calibrated? When I ran today 3/4 of a mile, the only thing that was measuring how far I ran was my foot strikes (pace). You CANNOT calibrate pace with pace. Therefore, there is no way to calibrate the system. Stated another way, if I measure 400 meters, using some undefined method that we agree to be accurate, and then I run it using my 3GS and Nike+ and at the end look at my phone to see that the app has only logged 350 meters, there is no way to tell the phone it is wrong. If I end the workout, it says that the phone had not calibrated because the distance was not sufficient. If I were to do it again and continue to run another 50 meters until the phone registers 400, it will "calibrate" the phone, but it is still inaccurate because I really ran 450 meters.

I'd like to know if anyone else has thought about this and if there is an answer that makes sense. I secretly hoped that calibration pulled from the phone's GPS, but I have been told time and time again that is not what happens by Apple and Nike techs. Further, if that was the case, why the hell wouldn't the 3GS tell you when your calibration was complete as opposed to letting you run right through the calibration distance? It just doesn't add up.

I find this whole thing very disturbing. I also find it a little nauseating that the Nano Nike+ software is more powerful and accurate than the app for my iPhone. Can someone please explain the logic here? I'm I missing something, or should I just buy in to the whole "the software knows what it is doing" argument - which is complete BS!

Thanks in advance for any assistance any of you can provide.
 
all I can add is that I bought me a 32GB 3GS and Nike+ for running, and have left the Nike device in a drawer since about a week after purchase. I just run outdoors and use Runkeeper Pro, which although is sometimes slightly off, has been much more accurate than the Nike+ device.
 
For me, the Nike+ with my iPhone 3GS has been pretty accurate. I usually run a track that is 1.3 miles and Nike+ says it's 1.23 miles. That's almost a tenth of a mile difference, but I'm not really sure how they calculated the track distance in the first place.
 
TL,DR !!!

seriously I cut and pasted your post into word = a 5 page double spaced document !!


From my brief reading i gathered this

a) why don't you try it with a real pair of nike+ supported shoes, maybe that pouch is whats throwing you off

b) From their own website it states that its only accurate to about 90% , and clearly states it doesn't use GPS, only the accelerometer on the nike+ chip

c) You feel like the nike+ programs says you are slower than you really are (edited :p )


Until they update the chip to have a real GPS+ pace integration, you shouldn't take the results too seriously, It's meant to be used for recreation, not for anything official

http://support.apple.com/kb/HT2293?viewlocale=en_US

Call me old fashion, but I prefer knowing how far I'm going to run and then just using a stopwatch to determine my pace
 
Lollicup, forgive the length of my post, but frankly after reading these forums for the last 2 years and seeing people bitch and complain without providing any real detail or proof, I thought I would go out of my way to show I put some brain power into this. To your point:

1) I'm happy to try Nike shoes, and said that in my post. I do hope that improves the accuracy. But my question is about calibration and how that works on the iPhone. I have a desire to understand that aspect of it.

2) Again, I am aware of this fact. My question is how do you calibrate pace using only time. It's not possible. Pace calibration requires time and distance. If the iPhone does not let you input or control the distance or use GPS, then I cannot see how calibration is possible.

3) Respectfully, you couldn't be more wrong. I am not a speed runner and have no desire to be. I run for fitness only and so that I can eat cheeseburgers like Jughead and Whimpy. I am only looking for an accurate measurement of the distance I run. I find it motivational. When I run 8.5 miles according to local running maps, my car, and Google Maps Online Pedometer, and my iPhone tells me I only ran 6.5, that is not 90% accurate, and that doesn't even make for an enjoyable recreational product.

At the end of the day, we are out running and getting a good workout. I am not denying that, but this is a technology forum and I feel like my question is legit.
 
OK, here is my take.

I use Nike+, but with their sportband. I also use RunKeeper Pro. I have found that the Nike+ is never off by more than 3/10 of a mile. Sometimes Nike+ says I have run farther than what RunKeeper says. Sometimes it is shorter. I keep using Nike+ because I like the Nike+ community and all the Nike's website has to offer, but rely on RunKeeper for better accuracy for training.

I ran into a similar issue as you with an older sportband, which ended up going bad. As far as your situation is concerned, when you got your replacement iPhone, did you restore from backup to the new iPhone? If you did, there may be something corrupt in the backup and I would recommend doing a complete wipe of the phone, restore the iPhone OS, but treat it as a new iPhone and don't let it restore from backup. Does that make sense?

As you have found in your research, Nike+ will never give complete accuracy as using the GPS, BUT it should be close enough casual runners and there is something clearly wrong with a component in your Nike+ chain. As I've said, I suspect there is some sort of software corruption.
 
Go to your local Apple Store and patiently explain everything that has happened. There is no reason for the system to be malfunctioning this badly. I haven't heard of any errors this big from anyone else I know, so I cant help you. Most people here probably don't even use Nike+. Good luck anyway!
 
Well add me to the list of people experiencing issues with Nike plus. You have described the same situation I encountered when using the Nike plus with my ipod. I opened a ticket with Nike. Never got a resolution. Did the recalibration, it never worked. I stopped using it to measure distance, just used it as a timer for my runs.

I had been using a shoe pouch. Thinking that may have been the issue, I bought the Nike shoes for the sensor. No difference, still crappy results.

Ended up buying a garmin 405 watch which has been flawless.
 
I have had no problem with mine. but i calibrated mine on a track. when i run sometimes i will drive my car the route and see what it says. they have been very close.
 
Don't worry I understand what you are saying. If during calibration there is no way to correct the results then that isn't calibration. That is just a Reading telling you how incorrect it is.

This is obviously a design flaw in the software. I don't get how everybody else seems to get such good results when the cannot calibrate. Our stride s not always the same so it needs to find an avg to work on.

Anyway goodluck and I say don't buy their shoes until the ability to calibrate s actually provided.
 
face the same problem

Hi,

I bought my 3gs last week, and am facing the same problem.

My usual running route is a 3km run to the office, at an average pace of 6'20 to 6'40 per km (this was captured using my IPod)- I did over 50 runs of the route this year- so trust me, I know my pace and I know my distance. :cool:

With the 3gs, my average pace has dropped to 7'30 to 7'50! And the distance recorded is shorter!

I tried calibrating at both, a treadmill and on the track, but I find this USELESS because of the same reason given earlier (it's the runner who should LOCK IN the distance, not the iphone).

And I do use Nike+ shoes..

Frustrated!
 
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