Calibrating the Nike+ Running App can improve the accuracy of your run data.
If you lose GPS signal during your run, the Nike+ Running App may offer you the option to calibrate your run by adjusting it to match your actual distance.
If you run outdoors with the Nike+ Running App and are able to maintain a GPS signal, the Nike+ Running App will calibrate the accelerometer automatically, with no action required on your part.
If you run indoors, make sure you set your workout up as an Indoor run in the Nike+ Running App run setup screen. You'll need to carry your device in your hand as you run.
Contact Nike+ Support for assistance. You can also give feedback or report a bug.
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