Modern Apple Watch models record overnight vitals and can alert you to significant deviations—like potential infection. A new Apple feature called “Training Load” helps you build fitness gradually, avoiding overtraining while ensuring enough exertion to see progress. These functions work together, and we’ve gathered eight tips on how to use them effectively.
1. Track Body Metrics While You Sleep
Overnight, the Apple Watch measures your heart rate, respiratory rate, temperature (Series 8, Ultra 1 and up), and blood oxygen saturation (Series 6 and up).
- Ensure Sufficient Battery & Proper Fit
- The Watch must have enough charge and remain on your wrist overnight.
- Confirm that you wear the band snugly, so sensors maintain skin contact—loose contact results in erratic readings.
- Enable Sleep Tracking
- On your iPhone, open the Watch app → My Watch → Sleep. Turn on “Track Sleep with Apple Watch” if not already set.
- It’s easier to configure via the Health app: under Discover → Sleep, define your sleep schedule, typical bedtime, and wake time.
- Use the Sleep Focus
- To gather full body measurements, the “Sleep” focus must remain active overnight. You can automate this with a sleep schedule in Health or enable it manually via the Control Center on your Watch.
- Check Your Watch’s Compatibility
- Apple Watch 9, 10, and Ultra 2 also analyse breathing disruptions like sleep apnea. Earlier models record fewer metrics.
Tip: If you share your bedroom with another person, that person might prefer the Watch’s subtle vibrations as an alarm (rather than a phone’s louder ring).
2. Examine Vital Signs on Your Watch
From watchOS 11 onward, the Apple Watch’s Vitalzeichen (Vitals) app charts nightly measurements—resting heart rate, respiratory rate, skin temperature, SpO₂, and more. After about a week of consistent sleep tracking, it can detect whether these values are “typical” for you or deviate significantly.
- Open the Vitals App
- In the watchOS app overview, find Vitalzeichen. Scroll for nightly or weekly graphs.
- Use the Calendar Icon
- Toggle between last night’s details or a weekly summary.
- Dock or Widget
- Add the Vitals complication to supported watch faces (e.g., Modular series), or use a Smart Stack widget.
3. Keep Body Metrics in Continuous View
Ziffernblatt (Watch Face) Complications
- Only certain watch faces support big rectangular complications that let you see the “Nightly Vitals” or “Weekly Vitals.” For Apple Watch Ultra, you can set them in the outer ring of Modular Ultra, so you don’t occupy a normal complication slot.
Widgets in iOS
- Because iOS has no dedicated Vitals app, you can view these metrics in the Fitness app or via a widget on your iPhone’s home or lock screen. Search in the widget library for “Health” → “Vitalzeichen.”
4. Get Alerts for Significant Deviations
If at least two of your nightly vitals deviate substantially from your typical baseline, watchOS can send a notification (unless you use a third-party app that triggers earlier). For instance, if you notice a spike in resting heart rate, body temperature, and respiratory rate, you may be coming down with an infection.
Keep in Mind:
- Apple emphasises that these alerts aren’t medical diagnoses; they’re more akin to “possible sign something’s up.” Alcohol or caffeine can also affect data, so interpret carefully.
5. Understanding the New “Training Load”
watchOS 11 and iOS 18 introduce Training Load, which estimates how your exercise volume compares over the last 7 days vs. the past 28 days. The feature helps gradually increase fitness without risking injury from excessive strain or losing out on gains by underexerting.
- Enable Training Load
- In the iPhone’s Fitness app → “Overview,” scroll down to “Edit Overview” → “Add…” and pick “Training Load.”
- On the Watch, open the Activity app (three ring screen), then tap the new top-right graph symbol.
- Reading the Graph
- A dotted coloured line (7-day) vs. a solid white line (28-day). Large gaps suggest you’re either pushing yourself far harder than usual (risk of injury) or not enough (reduced fitness improvements).
- Ziffernblatt or Widget
- In watchOS, place a big rectangular complication on certain watch faces (e.g., “Modular”). You can also add a “Fitness” widget in iOS to glance at your load.
- On the Apple Watch Ultra, you can attach it to the outer ring as a separate gauge next to your night Vitals.
6. Assign “Effort” to Workouts
For sports like running, cycling, or walking, the Watch automatically estimates intensity. But certain workouts (strength training, yoga, etc.) need a manual “RPE” (rate of perceived exertion) entry.
- In the Fitness App → ‘Training Load’ → ‘Recent Workouts’
- Tap a workout missing an effort value. The scale from 1–10 (easy to extremely hard) helps Apple compute your overall load.
- Watch Reminders
- Turn on “Effort Prompt” in Watch settings under “Workout” → “Prompt to Rate Effort,” so you can add the effort after each session.
7. Relate Training Load to Body Vitals
Open the Fitness app → “Training Load” → bottom of the graph. Tapping any daily point shows your health metrics from that night. This insight helps see how a high-intensity session influences your overnight temperature or resting HR. For instance, a big hill run might temporarily bump your respiratory rate or resting pulse.
8. Combined Approach for Overall Wellbeing
- Overnight Monitoring to catch deviations, spot possible illness.
- Training Load to structure your workouts.
- Manual Effort Ratings to track sports beyond what Apple Watch can automatically measure.
- Vitals on iPhone so you can quickly identify patterns over weeks or months.
Conclusion
Apple’s recent watchOS updates have turned the Watch into a more sophisticated tool for health and fitness monitoring, from overnight vitals to daily training loads. With these eight tips, you can better interpret your body’s signals—spotting early signs of stress, infection, or overtraining—and keep workouts tailored to your goals. Plus, new on-watch complications and phone widgets ensure your progress is never more than a glance away.
