The three colorful rings on an Apple Watch represents various Fitness Goals. The Red Ring is the Move Goal that displays how many active calories you have burnt so far. Active calories are the ones that you burn by moving around, standing, climbing stairs, exercising, and the like. The Green Ring is the Exercise Goal that indicates how many minutes of brisk activity you've done in a day. By default, the Exercise Goal is set to 30 minutes. Lastly, the Blue Ring is the Stand Goal which shows the hours for which you've stood up and walked for at least 1 minute. For someone who's using a wheelchair, the Stand ring changes to Roll ring, showing hours in which, you’ve pushed around for at least 1 minute.