Overview
The Heart Rate Zones booster analyses your heart rate stream and calculates time spent in each training zone (Zone 1 through Zone 5). It generates a visual breakdown with emoji progress bars showing the intensity distribution of your workout. This is particularly useful for endurance athletes who want to share their training zone distribution on Strava.
Configuration
Max Heart Rate (max_hr)
Your maximum heart rate in BPM. Default: calculated as 220 - age (from your profile). Override this if you know your actual max HR from a lab test or field test.
Practical tip: Using the generic 220 - age formula can be inaccurate by ±10–15 BPM. If your zone data consistently looks wrong (e.g., you're always in Zone 5 despite feeling comfortable), you likely need a lower max HR value.
Zone Model (zone_model)
| Option | Zone Boundaries |
|---|---|
| 5-Zone (default) | Zones at 50%, 60%, 70%, 80%, 90% of max HR |
| 3-Zone (simple) | Easy / Moderate / Hard |
| Custom | Define your own boundaries |
Display Style (style)
| Option | Example |
|---|---|
| Emoji Bars (default) | Zone 3: 🟨🟨🟨⬜⬜ 22 min |
| Percentage | Zone 3: 42% (22 min) |
| Time Only | Zone 3: 22 min |
Bar Length (bar_length)
Only visible when Style = "Emoji Bars"
Number of emoji squares per bar. Range: 3–10 (default: 5).
Data Requirements
- Heart rate stream — Second-by-second or higher resolution HR data required. Summary HR (avg/max only) is not sufficient for zone calculations.
- Sources like Garmin, Fitbit, and Strava typically provide HR streams. Hevy does not.
How Content Appears
On Strava (description)
💓 Heart Rate Zones
Zone 1 (Recovery): 🟦🟦⬜⬜⬜ 12%
Zone 2 (Aerobic): 🟩🟩🟩🟩⬜ 28%
Zone 3 (Tempo): 🟨🟨🟨🟨🟨 38%
Zone 4 (Threshold): 🟧🟧⬜⬜⬜ 15%
Zone 5 (Max): 🟥⬜⬜⬜⬜ 7%Tier & Access
Available on the Hobbyist (free) tier.
Common Issues
All time in one zone — Your max_hr is probably wrong. If set too high, all effort lands in Zone 1–2. If set too low, everything is Zone 4–5. Adjust your max HR based on actual testing.
No output / "Insufficient HR data" — The activity needs an HR stream, not just avg/max values. Sources that only provide summary HR won't work with this booster.
Bar length not changing — Only applies when Style = "Emoji Bars". No visual effect with Percentage or Time Only styles.
Zone distribution doesn't match my watch — Different platforms use different zone models. Your Garmin may use lactate-based zones while FitGlue defaults to percentage-of-max zones. Set up Custom zone boundaries to match your watch's zones if exact parity is important.
Dependencies
- Requires HR stream data on the activity
- No integration dependencies