With the Loop, Polar is clearly coming for Whoop. Like its inspiration, the Polar Loop is a screenless fitness tracker that measures your activity, heart rate, and sleep with a design that combines a ...

The Polar Loop (Gen 2) is a solid piece of hardware, but it's by no means a straightforward subscription-free alternative to Whoop. That might be the case for some existing Polar watch users craving a ...

Heart rate is one of the most valuable physiological metrics for runners because it provides objective real-time insight into how hard your body is working. Unlike pace or distance, which are external ...