Pretty much every fitness tracker and smartwatch has an optical heart rate sensor, but they're not always perfectly accurate.

When training, there’s seriously nothing worse than looking down at your watch and seeing an erratic heart rate reading. This usually means that your watch has lost all contact with your chest ...

You can also use it alongside the Garmin Connect app (free on Android and iOS), where you can view your heart rate data. You can also use the HRM-Fit chest strap with Zwift or Strava or other ...

The Garmin Venu 3 won me over as best fitness ... right in line with my control device through it all (the Polar H10 Chest Strap). Unlike other trackers that can make it hard to break down what ...