I use a Garmin Forerunner 55 fitness tracker. It's primarily for running, but can be used for many other fitness activities. It also tracks, or can be used to track: heart rate, sleep, calories, stress, hydration, daily steps, weight. And it does all this without having to pay for any subscription. Additionally, I can sync my Garmin data with my iPhone's health app, which provides further health data. If you have an iPhone, the Health app can be pretty useful on its own.