Start moving with a fitness tracker
These tools can help motivate you and tell you if you're exercising at your optimal heart rate.
You've probably seen people wearing digital fitness trackers, small gadgets that come in wearable styles such as wristbands and pendants or handheld versions you can slip into a pocket. Why are they popular? The devices record your workout data, and they track your progress on those measures. "We've seen them make a big difference in people's workouts," says Linda Arslanian, director of rehabilitation services at Harvard-affiliated Brigham and Women's Hospital.