Calculator Inputs
Example data table
| Scenario | Input | Method | Sample Zone 2 |
|---|---|---|---|
| Cardio | Age 30, HRmax estimate | %HRmax | ≈ 114–133 bpm |
| Cardio | HRmax 190, Resting 60 | HRR (Karvonen) | ≈ 138–151 bpm |
| Cycling | FTP 220 W | %FTP | ≈ 123–165 W |
Safety note
Formula used
How to use this calculator
- Choose a mode. Pick heart rate or cycling power, based on your training.
- Pick a method. Use HRmax percent for simplicity, HRR for personalization, or LTHR if you know your threshold.
- Enter accurate values. Use recent tests when possible. Keep resting HR measured the same way each time.
- Calculate and review. Your zone table appears above the form.
- Export your zones. Download CSV for logs, PDF for printing.
Why training zones improve results
Training zones translate effort into measurable targets. When Zone 2 work stays mostly aerobic, athletes can accumulate more minutes with lower fatigue. For example, a 30‑year estimate of 190 bpm gives a Zone 2 band near 114–133 bpm. Holding that range supports steady endurance adaptations while keeping recovery costs predictable.
Selecting the right calculation method
Percent of maximum heart rate is quick and consistent for beginners. Heart rate reserve adds your resting heart rate, which often shifts zones upward for fit users. If HRmax is 190 and resting is 60, HRR equals 130, so a 60–70% Zone 2 becomes roughly 138–151 bpm. Threshold-based zones work best after a recent threshold test.
If you only have a watch, begin with HRmax percent, then switch to HRR after two consistent weeks of morning resting readings. Save exports to track how your bands shift after testing.
Reading the zone table correctly
Each row shows a lower and upper boundary for a specific purpose. Zone 1 is recovery and warm-up. Zones 3 and 4 are commonly used for tempo and threshold intervals that build sustainable speed. Zone 5 is short, very hard work. Use the lower edge for long sessions, and the upper edge for short repeats, especially when you are fresh.
Heart rate lags changes in effort, often 30–60 seconds. In heat or hills, use breathing and talk test to confirm the zone. Power changes instantly, so keep interval targets in watts, and monitor recovery heart rate.
Keeping inputs accurate over time
Zones drift as fitness changes. Recheck HRmax estimates when age changes, and update resting heart rate if sleep, stress, or illness alters it. For cycling power, retest FTP every 6–10 weeks during a build phase, or after a training break. Small updates can prevent training “too hard” or “too easy” for weeks.
Example weekly application
A balanced week often combines easy volume, one threshold session, and one higher-intensity session. A simple structure is three Zone 2 days, one Zone 4 day, one Zone 5 interval day, and two recovery days. Keep most minutes easy; many endurance plans target about 70–85% of weekly time in Zones 1–2.
FAQs
Which method should I choose first?
Start with percent of maximum heart rate if you are new or lack testing data. Use HRR when you have a reliable resting heart rate. Use threshold-based zones when you have a recent threshold test and want tighter pacing.
Why do my heart-rate numbers change day to day?
Heat, dehydration, stress, poor sleep, and caffeine can raise heart rate at the same pace. When that happens, aim for the effort and breathing cues of the zone, and reduce intensity or extend warm‑up time.
Can I apply these zones to walking, rowing, or gym circuits?
Yes for steady aerobic work in any cardio mode, as long as you can measure heart rate or power. For strength training, intensity is better guided by reps in reserve and rest times than heart-rate zones.
How often should I update my threshold or FTP?
During a structured block, recheck every 6–10 weeks, or sooner after illness or a long break. Recalculate zones after retesting so sessions stay matched to your current fitness.
Why do some power zones show an open-ended upper limit?
Very high sprint efforts can exceed typical testing ranges, so the top band is shown without a hard ceiling. Use it for short bursts, and focus on form, safety, and full recovery between sprints.
Is it necessary to train in the hardest zone every week?
No. High-intensity work is effective but stressful, so keep it limited and recover well. Many athletes do one hard interval day weekly, plus endurance sessions, and add intensity only when sleep and soreness are stable.