This product automatically detects exercise, counts repetitions and tracks muscle fatigue with the help of Apple Watch, accurately finding the fatigue points. It can read wrist movements, heart rate and rhythm to identify exercise movements and record them. It runs on the wrist without a phone and without settings, etc. It automatically records the number of repetitions, speed and heart rate of each group of movements without manual operation, and can also inform users of their exercise status and whether they need to increase the intensity. It shows the exercise effects by muscle group and explains the reasons for plateaus.