Personalized activity intelligence: A better way to track exercise?

By: Julie Corliss, Executive Editor, Harvard Heart Letter Perhaps the best-known problem with fitness trackers is that people often retire them to a junk drawer after a few months, once their novelty wears off. But that’s not the only issue with these devices, which are typically worn around the wrist or clipped to clothing. Sure, they’ll count your steps, display your heart rate, and even estimate how many calories you’ve burned, although you’ll…