Hi
To credit progress toward your Exercise goal, the Activity app aims to identify activity that equals or exceeds the intensity of a brisk walk. The definition of this varies, depending upon your personal information. To check that your personal information is accurate:
- On your iPhone, in the Watch app, go to: My Watch tab > Health > Edit.
For the purpose of awarding Exercise credit during general daily wear, the Activity app relies on arm motion (measured by the accelerometer). For the best results, allow the arm on which you are wearing your watch to swing naturally as you exercise. If you did not record your activity as a workout, this was the only information that was taken into account when awarding Exercise credit.
In addition to using accelerometer data, the Workout app can also use data from the heart rate sensor and - for outdoor activity - GPS data (when available via the paired iPhone).
The heart rate sensor is likely to give better results for workouts that involve rhythmic (eg running) rather than irregular movements (eg weights). For the best results, your watch should sit snugly against the top of your wrist. For the best performance, Apple suggests that you consider tightening your watch band before workouts and loosening it again afterwards. For weight training or other activities that involve flexing your wrist, it may also help to move your watch further up your arm.
If you would prefer to record the full durations of workouts as Exercise regardless of their intensity levels, track them via the Workout app using Other as the activity type. This will credit one minute of Exercise for each full minute of the workout.
More information:
Use the Activity app on your Apple Watch - Apple Support
Use the Workout app on your Apple Watch - Apple Support