Tomtom runner 3 cardio sports watch say goodbye to your chest strap and train with built in heart rate monitoring on your wrist see your heart rate on your wrist track your heart rate with the built in heart rate monitor no chest strap needed never run the same route twice upload trails to your watch to discover new routes be confident that you will find your way back to the start run smarter with real time information and track all your sports just look at your watc