By default, Polar enables autocalibration for Stryd when you first pair your Stryd, which means that Polar uses its GPS to determine the accuracy of Stryd. We typically recommend disabling autocalibration. When you follow the instructions below and set the calibration factor, autocalibration will be disabled.
The calibration process is sport profile-specific. This article explains how to set the Polar calibration factor for the "Running" profile. If you use "Treadmill Running" or other profiles.
The best way to calibrate your watch correctly is to run a known distance to check the accuracy of your Stryd. You can find the detailed instructions to run a known distance and test your Stryd here: Distance and Calibration.
Before you go to the track, make sure your Polar is set up correctly. Follow the following steps:
1. Make sure your Stryd is paired with your Polar watch. If Stryd is not yet paired with your Polar, the menu option in step 4 does not appear.
2. On your watch, select Start Training > Running
3. You will see a small wheel on the top left. Select that to change the setting for the Running profile.
4. Select Calibrate stride sensor > Calibration factor (note: the watch must be paired with Stryd and connect to your Stryd before this option appears).
5. Set the calibration factor to 1.000. If you simply want to disable autocalibration, you can stop here without doing a test.
6. Do the test
7. Once you have completed the test, calculate the calibration factor for your Polar watch. The calibration factor is calculated as a ratio of the actual distance to the uncalibrated distance. Example: you run 1200m, and Polar with Stryd measured a distance of 1180m. Calculate your calibration factor as follows: 1.000*1200/1180 = 1.017.
8. To set the calibration factor, repeat steps 2 through 5 listed above, setting the calibration factor as calculated in step 7.