Distance and Calibration

Stryd is very accurate out of the box, and calibration is not required for most runners. If you are interested in verifying this, you need to test it against a known distance. We recommend using a track. From experience, we know that even certified competition tracks can be off up to 1%.

Measure the distance of the track

• We recommend measuring on the inside line of lane 2 (depending on lane width, the distance for a certified track should be about 405.8 meters).
  • It is near impossible to run exactly 400 meters on the track, as the centerline of the track is 20 cm from the inside line of lane one and is almost impossible to follow exactly (on rare occasions it will be 30 centimeters away if the curb is raised). 
• You must use a reliable distance wheel and a steel ruler. Do not use a GPS device. We have found tracks that are 1% off the reported 400-meter distance. We have also used certified courses that were marked poorly or did not adhere to standards so it is important that you know the exact distance you ran with your own trusted measurement.
  • Cheap measuring wheels cannot be used as they are inaccurate. You need to purchase a premium wheel. Example for an inaccurate measuring wheel: Keson RR310, and an accurate one: Keson mp401 metal frame measuring wheel. Our testing showed that the inaccurate wheel can be off by multiple meters per lap.
  • Unwind your steel ruler (i.e. 10 meters or 30 feet) and verify the accuracy of your distance wheel along the steel ruler. Determine the accuracy of the measuring wheel (cheap measuring wheels may pass this test but will still be inaccurate in the turns).
  • Measure the distance of the inside lane of line 2.
  • Make note of the exact distance of the track/path. Be sure to clearly mark the start and finish lines.
• An article about track geometry: http://datagenetics.com/blog/may12015/index.html
• You can select a different line if you prefer. Below is a table to show the distances of the various lines of a track:

Ensure Stryd is firmly on the shoe

• You must make sure Stryd is attached to the shoe properly. Slide Stryd’s clip under multiple rows of laces to ensure a snug fit and Stryd must be centered on your foot. If you are running counterclockwise on the track, make sure Stryd is on your left foot (or right foot if you are running clockwise).
• If you are concerned about accuracy during a race, do the track test with shoes you typically use during an event

 Pair Stryd as a foot pod with pace/distance set to always

• Connect Stryd to your watch (you can use any watch that supports foot pods). Most watches allow you to force the foot pod to be used for speed and distance (and not use the GPS). (Find proper pairing instructions for your Garmin watch here>>)
• There will be a calibration option. Set calibration to manual. Set the calibration factor to 1.000 (on Polar and Suunto), or 100 (on Garmin).
• Turn GPS off

Locate the starting line and prepare to start

• Do a quick 60-second jog before you start the effort to ensure Stryd is awake. You should start your run within two minutes after the quick jog.
• Put your left foot on the start line. 
• If you measured the length of the track, follow the track as you measured it in step 1 (your Stryd should always be in the middle of the line).

Do the run

• It is important to treat this test like a completely separate run
• Start with your Stryd foot on the starting line and wait for 10 seconds
• We recommend doing an 8-lap (3248 m) run (do not walk)
• It is recommended to run at your race power target for the test.
• Be sure to stay on your marked path. Every foot strike must land on the marked path. If this does not happen, your testing result will not be relevant because we will no longer know the exact distance that you ran.
• No need to hit the lap button each lap as it is not possible to always hit the lap button at the correct point.

Cross the finish

• Stop immediately on the line. Be sure to step on the finish line with the foot that has Stryd on it and do not take a step further. This is a must. Wait 10 seconds before hitting either the lap marker or stopping the watch after standing still on the finish line. 

Sync the watch / Sync the foot pod

• Sync the watch with your online platform (i.e. Garmin Connect). Check the exact distance as measured by the watch for your eight laps.
• Optionally: sync the foot pod with the Stryd mobile app as well, so you can compare the distance measured by the watch with data straight from Stryd (note that Stryd does not record laps). Note that you should set up a secondary Stryd account to avoid that your data duplicates or merges. 
• If you want to update the calibration, see fine-tuning the accuracy of my Stryd.