iPod Which data is more accurate, treadmill or Nike+ Kit?

DVNIEL

macrumors 6502a
Original poster
Oct 28, 2003
927
511
California
I went to the gym this morning for a quick workout. Even though the treadmill has a screen with my running stats on it, I used my Nike+ kit so I can have a record of it. At the end of my run, the treadmill said I had ran about 2.3 miles, but my Nike+ iPod told me that I had ran a total 3.02 miles, which do you guys believe is more accurate?
 

atszyman

macrumors 68020
Sep 16, 2003
2,437
1
The Dallas 'burbs
I'd bet the treadmill would be more accurate since it knows the size of it's rollers and has only to count revolutions of the roller to know exactly how far the belt has gone (assuming no slipping). The Nike system as I understand it would be measuring your stride length so if that varies on pavement vs treadmills it could easily be off for treadmill running.
 

ChickenSwartz

macrumors 6502a
Jul 27, 2006
903
0
Treadmill should be fairly accurate. It measured based on how many times the belt turned, a constant. Whereas the Nike+ thing is based on strides alone. If you take different length strides then the Nike+ will be off. I think in general you will tend to take longer strides on a tredmill becasue you don't have to worry about what is coming up on the path.
 
L

Lau

Guest
I would believe the higher number, because it would make me feel better. ;)
 

tobefirst

macrumors 601
Jan 24, 2005
4,066
1,168
St. Louis, MO
To play devils advocate...

A treadmill doesn't exactly have to be accurate. Sure, it can do a great job of counting the number of times the tread has gone around and get a good idea of that distance. But the way that someone runs on a treadmill can make a difference in how much of that distance is actually "ran," if that makes any sense.

The Nike kit doesn't just count the number of strides and multiply it by a constant; it is not a pedometer. It is an accelerometer that can measure different distances in stride.

All that said, I'd still expect the treadmill to be more accurate.
 

meelash

macrumors member
Aug 7, 2008
56
0
To play devils advocate...

A treadmill doesn't exactly have to be accurate. Sure, it can do a great job of counting the number of times the tread has gone around and get a good idea of that distance. But the way that someone runs on a treadmill can make a difference in how much of that distance is actually "ran," if that makes any sense.
It really doesn't.

The Nike kit doesn't just count the number of strides and multiply it by a constant; it is not a pedometer. It is an accelerometer that can measure different distances in stride.
I'm pretty sure this is not even physically possible.
 

Policar

macrumors 6502a
Nov 21, 2004
630
4
To play devils advocate...

A treadmill doesn't exactly have to be accurate. Sure, it can do a great job of counting the number of times the tread has gone around and get a good idea of that distance. But the way that someone runs on a treadmill can make a difference in how much of that distance is actually "ran," if that makes any sense.
Explain. I'm still trying to wrap my ahead around this and can't.
 

puma1552

Suspended
Nov 20, 2008
5,559
1,919
Explain. I'm still trying to wrap my ahead around this and can't.
holy thread bump batman

but as to your question, if someone took a stride, then sat idle while their foot moved towards the back of the treadmill before taking another stride, the distance ran would be less. in reality, nobody on a treadmill would actually do this.