Revision as of 11:59, 23 October 2012

A picture of the Garmin and Polar Footpods with an AA battery for size comparison.

A Footpod is a small device that measures pace and distance while running or walking. These Footpods contain accelerometers that calculate the movement of your foot, providing an accurate measurement across a broad range of paces and stride lengths. A Footpod does not simply measure each stride, which would be wildly inaccurate. If you have a Garmin Watch then a Garmin Footpod is an excellent upgrade.

1 Accuracy

Out of the box, a Footpod is typically accurate to 90+% and after calibration this typically improves to 98-99%. This compares well with the accuracy of GPS which is 97-98%. However, a Footpod only gives you this accuracy on smooth surfaces where your stride is reasonably predictable. If you do trail running, I found the accuracy can be rather patchy. Of course if you're running a twisty trail with tree covered, you may find the accuracy of GPS dropping to 80-95%. I have found that a Footpod provides vastly more accurate information for your current pace compared with GPS. While the errors in the GPS signal even out over the course of a run, they can result in a current pace that is inaccurate by 1-2 minutes/mile.

2 Calibration

You can calibrate a Footpod against a known distance, or against GPS. In both cases a longer distance will provide greater accuracy as small variations will even out. I have written a Garmin Foot Pod Calibration utility to simplify the process. Calibrating against a known distance is far superior to calibrating against GPS because GPS has its own level of inaccuracy.

3 Cadence

The Footpod will provide an accurate display of your Cadence, which is a critical and often overlooked aspect of running.

4 Using a Garmin Footpod

If you have a Garmin 910XT, 310XT or 610 then it is possible to display your current pace from the Footpod while getting other data from the GPS. I believe this is the optimal configuration for most runners. In addition, I found that turning the GPS off and relying on the Footpod dramatically increases the battery life of a Garmin watch.

5 Troubleshooting

There are relatively few things to go wrong with the foot pod.

• Make sure the Footpod is attached to the same position on the shoe each time you run.
• The Footpod needs to be reasonably well attached so that it moves with your foot. If it's flapping around you get inaccurate readings.
• The most common problem you have with the Footpod is a low battery level. A low battery warning should be displayed on your Garmin watch, but I've had problems before the battery warning was displayed.
• If you're still having problems after replacing the battery, then the Footpod has probably failed. I've had this happen to me twice, which may just be bad luck.