This is an unusual post for me, because it amounts to an advertisement for two corporate giants: Apple and Nike. But I’m enthusiastic about the Nike + iPod system, which enables my running shoe to communicate with my Nano.
A sensitive piezoelectric accelerometer monitors your footstrike when you walk or run and determines the amount of time your foot spent on the ground. This contact time is directly related to your pace. (emphasis added)
However the device works, there’s no need to estimate the length of your stride, which will vary as you run (depending on how tired you are).
When you’re stationary, your Nano isn’t able to locate the transmitter. You walk around when you’re setting up your workout, until the device has been located.
Nike says the battery is good for 1,000 hours. It goes into stand-by mode when it’s not in use to conserve battery life. There is a way to turn the transmitter off and on, but you would have to remove it from the shoe each time. Most people will just leave the power on between runs.
You don’t necessarily need a Nike shoe:
I switched it to a pair of Adidas. First I tried just putting it inside my sock …. No information transmitted to the receiver. Next I tried slipping it between the laces and tongue; I couldn’t feel it at all, it stayed in place, and it transmitted just as well as in the Nike pocket. So much for “needing” the special shoe. I think the bottom line is it has to be relatively horizontal … not vertical (as it was in the sock). The user’s guide specifies which side (the flat rather than the rounded one) has to be up.
But it seems that you still need a Nano — other iPods don’t have the software required. “Nike + iPod” appears as a new menu item on the Nano: