The Apple Watch delivers industry-leading health monitoring, GPS tracking, and cellular connectivity, but intensive workouts or long travel days can strain its battery. In watchOS, Apple provides Low Power Mode and specialized Workout Battery Optimizations. Rather than shutting down core functionality like older Power Reserve modes, modern Low Power Mode keeps step counting, activity rings, and workout tracking fully functional while temporarily suspending non-essential background processes and sensors.
Understanding What Low Power Mode Disables and Preserves
Low Power Mode selectively pauses high-drain features while maintaining essential health tracking:
- Disabled Features: Always-On display, continuous background heart rate measurements, blood oxygen readings, background heart rate notifications (high/low/irregular rhythm), and auto-workout detection prompts.
- Preserved Features: Step counting, elapsed workout time, calories burned, heart rate tracking during active workouts, emergency SOS, fall detection, crash detection, and local alarm notifications.
- Cellular & Wi-Fi Throttling: When your iPhone is not nearby, cellular connections are checked periodically rather than maintained continuously, unless an active call or stream is initiated.
Enabling Low Power Mode on Apple Watch
You can activate Low Power Mode manually at any time via Control Center or Settings:
- Press the Side button (on watchOS 10 and later) to summon Control Center.
- Tap the Battery percentage tile.
- Toggle the Low Power Mode switch to On.
- A descriptive summary screen appears detailing affected functions. Scroll down and choose:
- Turn On: Keeps Low Power Mode active indefinitely until manually disabled or until the watch charges to 80%.
- Turn On For: Enables the mode for a designated duration (On for 1 Day, On for 2 Days, or On for 3 Days).
- A yellow circle badge appears at the top of the watch face, confirming activation.
Configuring Automatic Low Power Mode During Workouts
For marathon runners, endurance hikers, and cyclists who want battery conservation without sacrificing daily Always-On display benefits:
- Open the Settings app on your Apple Watch.
- Scroll down and select Workout.
- Toggle Low Power Mode to On.
Whenever you start an outdoor run, walk, or cycling session in the Workout app, the Apple Watch automatically engages Low Power Mode. Once you tap “End Workout”, the watch instantly resumes normal Always-On display and background telemetry.
Enabling Fewer GPS and Heart Rate Readings for Ultra Workouts
On Apple Watch Series 8, Apple Watch SE (2nd generation), and Apple Watch Ultra models, watchOS includes an advanced power tier specifically engineered for ultra-endurance athletes:
- In Settings > Workout, ensure Low Power Mode is enabled.
- Locate and toggle Fewer Heart Rate and GPS Readings to On.
Under this mode, heart rate readings are sampled once per minute instead of continuously, and GPS location points are captured periodically rather than every second. This dramatically extends battery performance (enabling up to 60–72 hours of continuous multi-day tracking on Apple Watch Ultra) while maintaining accurate total distance and elevation metrics.