Heart Rate Zones Explained: How to Train and Film in Every Zone

Heart rate zones are one of the most powerful tools in endurance training — and one of the most misunderstood. If you're using an Apple Watch and filming your workouts, displaying your zone on screen gives viewers (and yourself) real context for effort rather than raw numbers.

The 5 heart rate training zones

Heart rate zones are typically calculated as a percentage of your maximum heart rate (MHR). A rough estimate for MHR is 220 minus your age, though individual variation is significant.

• Zone 1 (50–60% MHR): Very light. Active recovery, warm-up, cool-down. Conversational pace.
• Zone 2 (60–70% MHR): Light. Aerobic base building. The 'fat-burning zone.' Sustainable for hours.
• Zone 3 (70–80% MHR): Moderate. Aerobic endurance. Can sustain for 30–90 minutes. Slightly labored breathing.
• Zone 4 (80–90% MHR): Hard. Lactate threshold training. Uncomfortable but purposeful. Typically intervals.
• Zone 5 (90–100% MHR): Maximum. Sprint efforts, VO2max work. Unsustainable beyond a few minutes.

Why Zone 2 training has become a cultural moment

Zone 2 training has exploded in fitness conversations thanks to sports scientists and longevity researchers popularizing aerobic base building. Many serious athletes and health-focused runners now structure 80% of their training in Zone 2. If you're creating content in this space, showing your Zone 2 HR on screen is immediately relevant to a large audience.

How FitCam displays heart rate zones

FitCam calculates zones based on your Apple Watch data and your age-based maximum heart rate. The zone displayed updates every second alongside your raw BPM. The zone indicator is color-coded in some overlays — making it instantly readable in the video frame even when the viewer isn't looking closely at the numbers.

Workout types and their typical zone profiles

• Easy run: sustained Zone 2, with spikes to Zone 3 on hills
• Tempo run: Zone 3–4 throughout
• HIIT / intervals: alternating Zone 5 efforts with Zone 1–2 recovery
• Heavy lifting: Zone 3–4 during sets, drops to Zone 1–2 between sets
• Yoga / mobility: Zone 1 throughout
• Spin class: covers all zones depending on interval structure

Using zone data in your content

Zone data tells a richer story than BPM alone. A video showing 45 minutes consistently in Zone 2 is a statement about training discipline. A video showing Zone 5 spikes during 200m repeats is a statement about speed work. This context makes workout content more interesting and educational — which is what drives sharing and saves.