In the HA community, there are treads about the Xiaomi treadmill:
We do not know of anyone wo confirms that the Xiaomi treadmill HA integration works. But there is code available to control the Xiaomi treadmill from a PC. Just google for it.
There are BLE treadmill sensors available. We have reviewed those on our site.
https://petergamma.org/how-can-we-get-the-most-accurate-readings-from-a-treadmill/
It should be possible to connect those over a Training tracker to Strava to Home Assistant:
But we do not know of any community which uses this path on a regular basis. We came to the conclusion, that an excellent component for this project is the Adafruit Pyloton Open Source BLE Bike computer:
The Pyloton solves problems discussed here on a fundamental level. The sensors of the Pyloton can be replaced by a foot pod. The Treadmill sensors reviewed on our site support the BLE foot pod protocol.
According to our own little experience, the setup described here is a very interesting setup which will find friends all over the world.