The Xiaomi Smart Band 9 is one of the cheapest fitness trackers that's worth buying, despite some rough edges.

Your watch already tracks heart rate, but turning on this view helps you adjust your workouts in real time. Here's how to do it.

If you’ve never run a half marathon, Laraia suggests assessing your current “easy” running pace and heart rate data. If a ...

Marathon fatigue is real, says Amanda Katz, a certified personal trainer and running coach in New York City. The first step ...