Physicist Wires His Hamster's Wheel to Auto-Post Runs to Strava

Thijs de Buck, an MRI physicist in Utrecht, built a homebrew telemetry rig around his 10-month-old hamster’s exercise wheel and pipes the results straight to a dedicated Strava account. A magnet on the wheel trips a hall-effect sensor to count rotations, an ESP32 microcontroller logs the data overnight, and a morning script on his laptop converts it into a Strava-compatible .FIT file and pushes it through the Strava API. He started with a cheap bicycle computer but ditched it after it kept dropping into standby whenever the hamster paused, and because it only reported total distance rather than the splits and pace he wanted.

The build grew well past its original scope. It now includes a live OLED speed readout, automated personal-best detection, and a bank of more than 100 randomized run titles. Auto-uploading via the API turned out to require a paid tier, so the hamster now has Strava Premium. The account drew over 1,200 kudos and 600 followers within a week, and the hamster cleared Strava’s 400-minute August challenge on day two, averaging nearly 10 km a night.

Beyond the novelty, it’s a tidy example of the low-cost sensor-to-cloud pipeline that defines hobbyist IoT: a few dollars of hardware, a microcontroller, and a public API are enough to instrument almost anything and stream it to a SaaS platform. De Buck, a runner sidelined by injury, says the next milestone is the hamster’s 20th activity, when Strava starts generating race-time predictions.