Smartwatches are supposed to be the future. You wear them on your wrist, and they tell you how many steps you’ve taken, how many flights of stairs you’ve climbed, and how much sleep you’ve had. They can track workouts and heart rates too.The problem is that these tools are inaccurate at measuring lower levels of energy expenditure, like walking or housework. But this doesn’t mean that they are useless. In fact, they can motivate you to stay healthy and move more. But you should always take their data with a grain of salt.