View Full Version : GPS and Foot Pod

10-28-2009, 08:15 AM

I sometimes run in NYC. When I do and am on the West Side Running Path along the Hudson River I get a good GPS signal. But when I am running in the streets of Manhattan and the buildings are tall the GPS signal can be intermittent (for obvious reasons). My questions is: When there is no GPS signal is the foot pod accurate? it still show's pace data when there is no GPS signal. Just wondering how accurate it is. usually my run will be a combination of GPS+Footpod and NO GPS+Footpod. I hope this makes sense. THank you for your help.

10-28-2009, 08:37 AM
I find that the default calibration of the foot pod is accurate for me when walking about 3 mph. The faster I go, the more off it becomes. So you might want to calibrate the pod on a track.


10-28-2009, 08:42 AM
Can you calibrate the foot pod on a treadmill? I don't have access to a track?

10-28-2009, 08:49 AM
You can, but it depends if your treadmill is accurate or not. If that calibration is comfortable for you, then go for it. :)


10-28-2009, 10:48 AM
You should really calibrate it outside. You don't need a track. Put it in the auto-calibrate mode, press the start button and run until it tells you to stop. Just make sure when you do this, you aren't running down the middle of the Manhattan sky scrapers. I have found I have to run a bit under 1/2 mile before it is finished. Ideally you would do this along a relatively straight path and away from tall obstacles like buildings and trees. It also doesn't hurt if you are slightly warmed up so you stride will most match your normal running stride.

Also, as for how accurate the default calibration is, I have to set my calibration factor to 920, meaning I am off by 8% from the default. The calibration does change slightly with conditions and your fatigue level as your stride changes slightly. Don't count on a treadmill calibration for running outside. One, your stride will be slightly different, and two, treadmills are notoriously inaccurate themselves.

10-28-2009, 11:52 AM
I really wonder if the footpod will help you unless you turn your gps off. It didn't help me at all in the Chicago marathon. The issue is that I don't usually lose the gps signal, but rather get reflected signals from buildings that make the device think that I am somewhere else. I don't see how the footpod could help in these cases. The Garmins are not sufficiently sophisticated to be able to differentiate between the reflected signals and the direct ones. I think that would add significantly to the cost.

if you zoom in on the following map in the area of miles one through four you can see how screwy the path looks. This is my Garmin data (310XT) from the Chicago marathon:


If you do totally lose the signal, then the footpod would come to your rescue.