Zone 2 training builds your aerobic base and improves fat oxidation. Here's how to calculate your Zone 2 range and log every session using just your iPhone.
Zone 2 — that easy, conversational, fat-burning intensity — only works if you actually stay in it, and most people drift too hard. Pulse Rate helps you find and verify your Zone 2 heart-rate ceiling so your easy days stay genuinely easy. This guide covers how to estimate the zone and use it.
The variation between heartbeats — your nervous system's report card.
Two metrics, one number. Why Pulse shows both — and which to watch.
Training-impulse: your weekly training load, in one chart.
Zone 2 = 60–70% of your maximum heart rate. A simple estimate: 220 minus your age. If you're 35, your max is ~185 bpm and your Zone 2 range is ~111–130 bpm.
Open Pulse Rate and take a resting measurement first thing in the morning. This baseline helps you track how your resting HR drops as your Zone 2 fitness improves over weeks.
After a Zone 2 session (easy run, bike, or walk), measure your heart rate with the camera immediately after. How quickly it drops is a reliable marker of aerobic efficiency.
Consistent Zone 2 training lowers resting heart rate over 6–12 weeks. Pulse Rate's trend charts let you visualize this progress clearly and stay motivated.
The same chart that lives on your iPhone's Progress screen — rebuilt so you know what you're looking at.
Outstanding score. Your key heart metrics are above normal.
Most healthy adults fall within this range.
Not necessarily alarming — but worth monitoring.
If this persists, please consult a healthcare professional.
TRIMP = duration × intensity. A 60-minute easy run scores about 70 TRIMP. A 30-minute interval session scores 110. Pulse adds them up daily and tells you when your week is too light, just right, or about to overcook you.
A common starting estimate is 60–70% of your maximum heart rate, where you can still hold a conversation. Pulse helps you log readings so you can refine that range against how your body actually responds.
Zone 2 builds aerobic base and mitochondrial efficiency with low recovery cost, which is why endurance coaches program so much of it. The benefit comes from staying in the zone, not pushing above it.
A healthy morning HRV trend confirms that all those easy aerobic hours are building fitness without digging a fatigue hole. Pulse charts HRV next to your training load so you can see the balance.
For live in-workout heart rate a strap is ideal, but you can use Pulse to verify your resting and recovery numbers around the session without any extra hardware.
You've already got the hardware — your iPhone. Pulse does the rest.
Free to download · Core tracking always free · iOS 15+