1) The Workout Detection feature is disabled by default. You can go to Settings > Workouts > Workout Detection and select a workout type to enable this feature.
2) After the selected workout is detected, the watch will automatically enable the corresponding workout mode and record the workout data. For outdoor sports, your workout route will also be recorded.
3) The Alert toggle is turned on by default. An alert pops up whenever the start or end of a workout is detected. When the Alert toggle is turned off, the workout data will be silently recorded in the background and the watch face will display the Workout icon to indicate the user is working out.
4) Sensitivity is standard by default. The higher the sensitivity, the faster it is to detect the start and the end of a workout.