I tested Google's Fitbit Air against the Whoop 5.0 to see which screen-free tracker delivers better value, comfort, and health insights for everyday users.

Add Yahoo as a preferred source to see more of our stories on Google. Using a chest strap heart rate monitor can give you accurate, actionable insights to help improve your running. What is the best ...

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