There are tons of wearables out there that let you track your activity and even your sleep. But when you're an elite athlete, you need to know more than just how many steps you've taken, how long you slept, or how much you "exercised." The Whoop Smart Trainer goes far beyond that, using a wrist-worn tracker to gather a bevy of physiological data. It keeps tabs on heart rate and variability, skin conductivity, ambient temperature, and, of course, motion. It uses all that to arrive at a Recovery score that give coaches and trainers — like those of LeBron James and Michael Phelps — an instant overview of the athlete's overall condition, so they can adjust their workouts, training schedule, and even playing time or rotations accordingly. Currently available for pro, college, and Olympic athletes, because all the data in the world isn't going to help your pickup basketball game.