Footpod

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A comparison of various Footpods, from left to right: MilestonePod V3, MilestonePod V3, Polar Stride Sensor (Bluetooth), Adidas MiCoach (Bluetooth), Garmin (Ant+), RunScribe, i-gotU (Bluetooth).

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. These first-generation Footpods can be quite accurate, but require calibration, and this calibration has to be repeated for different shoes. The Stryd footpod is a second-generation Footpod and it's so accurate it doesn't require calibration. The first generation Footpods use a 3-axis accelerometer, where second generation Footpods typically use 9-axis sensors which combine accelerometers, gyroscopes, and magnetometers for far greater accuracy. (This page focuses on the first generation Footpods, though Stryd is far superior.)

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. You need to make sure the Footpod is well attached to your shoe; if it's bouncing about the accuracy will be poor. 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 Footpod Position

To get the most accurate reading, make sure the footpod is in the same position each time you use it. Moving the footpod around will change the calibration factor, as will changing to a different type of shoe.

4 Cadence

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

5 Using a Garmin Footpod

If you have a Garmin 910XT, 310XT 610, Epix, or 920XT then it is possible to display your Pace From A 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.

6 Bluetooth Footpods

There are a number of Bluetooth Footpods on the market that I've tested.

  • The Stryd footpod is vastly superior to any other footpod, but also a lot more expensive. Even at its higher price, it's great value for money.
  • The MilestonePod is the best option if you're not going for Stryd (and arguably is worth having for tracking shoe mileage even if you have Stryd.) MilestonePod has great compatibility and accuracy.
  • While the Adidas Speed Cell is accurate, it doesn't work well with Polar devices and is more expensive than the MilestonePod.
  • The Polar Stride Sensor is large and is not as accurate as the other options. It's only worth considering if you have a Polar watch, and even then, there are better options.
Stryd MilestonePod Polar Stride Sensor Adidas Speed Cell
Polar M400 Works Works Works The watch needs to be paired with a Polar Stride Sensor to activate the configuration menus. Provides cadence, but no automatic calibration or stride length.
Polar V800 Not compatible Works Works The watch needs to be paired with a Polar Stride Sensor to activate the configuration menus. Provides cadence, but no automatic calibration or stride length.
Suunto Ambit3 Peak Review Works Works Works Works
Suunto Spartan Ultra Review Works Works (Calibration in app) No Calibration No Calibration
Garmin Fenix 5X Review Works Works Works Works

7 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. See below for details.

8 Footpod Failure

I've found that the Garmin Footpods consistently fail after about 12 months of use. This is around 4,000 miles of running for me, but I don't know if the failure is due to the distance covered or the time. The initial symptoms are similar to a low battery, with the Garmin watch having problems detecting the Footpod. If you replace the battery and still get connectivity problems, then you may have a failing Footpod. The key symptom I've found is that the Footpod starts reporting an unreasonable pace, such as running a 3:00 min/mile pace. I've also had the Footpod cause the GPS to think I'm no longer moving, so the distance display does not increase and the average pace drops steadily. I'm now on my fourth Footpod and I've had to accept that they are consumable items.

9 RunScribe and MilestonePod

RunScribe make Footpods that measure a wide range of biomechanical data in addition to pace and Cadence, including Braking G's, Impact G's, Ground Contact Time, Foot Strike, and more. MilestonePod makes a Footpod that makes it easy to record the mileage on your shoes, as well as recording some of the data that RunScribe records. I love both devices, but they have different focuses. RunScribe is about detailed, accurate data, where MilestonePod is about recording mileage while giving some simpler, but useful data.