Garmin Sleep Tracking: How to Use Your Data to Train Smarter

Good training isn’t just about what happens in the gym, it’s about how well you recover between sessions. That’s where sleep tracking can become a game changer.

If you use a Garmin watch you have an amazing resource sitting on your wrist. The trick is understanding what those numbers mean and how to use them to improve your training, recovery, and results.

1. Sleep Stages: Light, Deep, and REM

Garmin breaks your night into stages, and each one plays a role in recovery:

• Light Sleep - Makes up most of your night. Helps your brain recharge, process information, and consolidate new skills.

• Deep Sleep - The body’s repair shop. This is where muscle tissue is rebuilt, growth hormone spikes, and you recover from training stress.

• REM Sleep - Where your mind resets. Critical for memory, learning, and managing emotional stress.

Coaching tip: If you’re lifting heavy or doing high intensity work, deep sleep becomes your best friend. More deep sleep = better muscle repair and performance gains.

2. Garmin Sleep Score: Your Recovery Snapshot

Garmin takes all your data, sleep stages, quality, and duration, and rolls it into a simple sleep score (0–100):

• 80–100: Optimal recovery - you’re primed to train hard.

• 60–79: Solid recovery - stick to your plan but listen to your body.

• Below 60: Your body’s under stress - lighten the load, add mobility, or take an active recovery day.

Coaching tip: Use your score as a guide, not gospel. The goal isn’t perfect numbers,  it’s spotting trends that affect performance.

3. Heart Rate Variability (HRV): Your Stress Gauge

HRV measures the variation in time between heartbeats. Think of it as a window into your nervous system:

• High HRV - Your body’s recovered, balanced, and ready to perform.

• Low HRV - Your system is under more stress, from training, work, or life.

Practical use:
If HRV is trending down for several days in a row, that’s a sign you might need:

• An extra rest day

• A lighter training session

• Better recovery habits (sleep, nutrition, stress management)

4. Resting Heart Rate (RHR): Your Recovery Baseline

Garmin also tracks resting heart rate overnight.

• Lower RHR - Better cardiovascular fitness and solid recovery.

• Sudden spikes - Can mean poor recovery, overtraining, illness, or high stress.

Coaching tip: Don’t stress over single - day changes. Watch your weekly averages instead, they will tell you the bigger picture.

5. How to Use Garmin Data in Your Training

Here’s how to actually apply the numbers:

• High sleep score + strong HRV trend - Go hard, push your training volume or intensity.

• Average score but flat HRV trend - Stick to your plan, but keep recovery habits dialled in.

• Low score + downward HRV trend - Pull back, focus on mobility, technique, or low-intensity conditioning.

Training smarter isn’t about doing less, it’s about knowing when to push and when to pull back.

6. What If You Don’t Track Sleep?

Not everyone wants to live by the numbers, and that’s okay.

• Pay attention to how you feel in training.

• Spot patterns: low energy, slower recovery, higher cravings, these often point to poor sleep quality.

• Use training logs to track how sleep affects your performance over time.

Wearables make it easier, but you can still train smarter without one.

Garmin sleep tracking isn’t about chasing perfect numbers, it’s about using insights to make better decisions.