Apple Watch Ultra fitness tracking and workout features
With its robust design and advanced sensors, the Apple Watch Ultra represents the pinnacle of wearable health technology. Continuous monitoring of physiological metrics, including VO2 max, a key indicator of cardiorespiratory fitness [1], makes it a powerful tool for fitness enthusiasts. Smartwatches are increasingly used for screening heart rhythm irregularities, with the Apple Watch's ECG capability enabling detection of tachyarrhythmias [2]. Given that palpitations affect up to 11% of the general population [3], such features are invaluable. Beyond tracking, the Apple Watch Ultra supports broader digital health interventions [4] and is part of the growing ecosystem of connected medical devices [5]. Its ability to monitor heart rate variability through advanced algorithms [6] further enhances its utility for personalized training. Whether you're an athlete or simply health-conscious, the Apple Watch Ultra offers comprehensive insights to optimize performance and well-being.
Practical Playbook
How do I set up the Workout app for strength sessions?
Open the Watch app on your iPhone, scroll to Workout. Tap Workout View and select 'Add Workout' then 'Strength Training'. Customize the metrics to show heart rate, active calories, and duration. Skip the auto-pause feature for lifting, you want continuous tracking.
Map the Action button to start a workout
The orange Action button on the Ultra is a game changer. Go to Settings > Action Button. Set it to launch a custom workout. I use it for Strength Training. One press and I'm in. No scrolling through menus mid-set.
Track recovery with HRV and resting heart rate
Apple Watch Ultra gives you HRV readings. Check them each morning before coffee. A consistent baseline is key. If your HRV drops 10-15 points from your 7-day average, you might need a rest day. Don't let a single low reading scare you off.
Compare route tracking for outdoor runs
The Ultra has dual-frequency GPS. For runners, this matters. It locks onto satellites faster and handles city canyons better. On a recent 10k run through downtown, my old watch lost signal twice. The Ultra nailed it. Use it to track precise route data for pacing analysis.
Common Mistakes
- Mistake
- Failing to map the Action button to anything specific for your sport.
- Why
- That customizable button is the whole point of the Ultra over a regular Watch. If you never program it to start a workout, mark a lap, or trigger a waypoint, you might as well be wearing a Series 8.
- Fix
- Open Settings > Action Button on your watch. Set it to start your most frequent workout type, or if you do intervals, set it to Segment or Lap. Takes 10 seconds and changes how you interact.
- Mistake
- Trusting the wrist optical HR sensor for sprint intervals or high-rep CrossFit sets.
- Why
- Optical HR has a 10-20 second lag during rapid heart rate changes. You'll see a reading from your last set while you're catching your breath, making interval pacing useless.
- Fix
- Pair a chest strap (Polar H10, Garmin HRM-Pro) via Bluetooth. The Ultra can broadcast HR from a strap to gym equipment, and you'll get real-time data that actually tracks your work intervals.
- Mistake
- Keeping always-on display on during ultramarathons or multi-day hikes.
- Why
- The Ultra's battery is good, but always-on screen drains it faster than you think. I've seen people hit 50% by mile 18 of a 50K because they never turned off the display.
- Fix
- Under Display & Brightness, switch to Raise to Wake for long efforts. You'll still get the orange action button on press, and battery life stretches to the advertised 36 hours.
- Mistake
- Ignoring the depth app when swimming in open water.
- Why
- The Ultra has a depth sensor that can auto-launch when submerged. If you don't enable that, you're missing a safety feature that could tell you exactly how deep you went on a dive or how far under you are during a swim.
- Fix
- Go to the Compass app and turn on the Depth gauge complication. Seriously, if you swim in lakes or oceans, this is a cheat code for knowing descent rate.
From the Dorsi blog
Three Apple Watch Numbers That Should Change How You Train (And One That Shouldn't)
Your Apple Watch tracks dozens of metrics. Three of them tell you something useful about today's training. One of them is loud, popular, and almost meaningless for lifters.
Apple Watch vs Garmin for training readiness
Garmin bakes Training Readiness and Body Battery into the watch. Apple Watch gives you the raw signals and lets an app decide. Here's which approach fits which athlete.
Your Apple Watch HRV Number Is Wrong — Here's the 60-Second Fix
The HRV in your Health app is a misleading average of inconsistent daily readings. Learn the 60-second Breathe-app protocol that gives you a real training signa
Sources we drew from
- 1
Lambe R et al. · 2025 · PloS one
VO2 max is a measure of cardiorespiratory fitness and a key indicator of overall health.
- 2ECG-Capable Smartwatches Can Induce Magnet Mode in Cardiac Implantable Electronic Devices.Peer-reviewed
Wegner FK et al. · 2026 · Journal of the American Heart Association
<h4>Background</h4>Smartwatches are increasingly used for screening of tachyarrhythmias and for ECG recording.
- 3
Gibiino F et al. · 2026 · Journal of clinical medicine
<b>Introduction</b>: Palpitations are one of the most common cardiovascular complaints, affecting approximately 6% to 11% of the general population.
- 4Opinion Paper: Smartwatches in Healthcare: Revolutionizing Health or Creating Data Confusion?Peer-reviewed
Gammie AJ et al. · 2026 · EJIFCC
Smartwatches have gained significant attention for their role in advancing digital health interventions and enhancing wellbeing.
- 5Role of the Pharmacist in Supporting the Use of Connected Health Devices: Example of Connected Watches.Peer-reviewed
Salomez-Ihl C et al. · 2026 · Pharmacy (Basel, Switzerland)
The use of Connected Medical Devices (CMDs) is growing significantly throughout the world.
- 6Low-latency HRV analysis from ultra-short ECG windows using a modular deep-learning framework.Peer-reviewed
Dobrosolski J et al. · 2026 · Scientific reports
We present a universal modular deep-learning framework and demonstrate its application to low-latency, streaming-compatible heart rate variability (HRV) analysis using RMSSD as an exemplar metric.
Just show up. Dorsi handles the rest.
- HRV-driven readiness — today's plan adapts to how recovered you actually are.
- Adapts every session — no decision fatigue, no second-guessing your numbers.
- Apple Watch native — log a set with your wrist, not your phone.