"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." If you are an athlete in training or simply keeping tabs on your vitals, measuring your heart rate is a ...

Building a real-life version of the Star Trek tricorder has been the goal of engineers and hackers alike since the first time Dr McCoy complained about being asked to work outside of his job ...

When it comes to exercising, your heart rate is the gold-standard metric to uncover how hard you're pushing. It tells you whether you're working aerobically or anaerobically, how your body is reacting ...