ZoneLab

One number — Accumulated Heart-Rate Minutes — connects your fitness, your target, and this week's load into one clear picture.

ZoneLab is a training partner, not a stopwatch — built around one idea: sustainable progress through correct training-zone alignment.

ZoneLab uses one number — Accumulated Heart-Rate Minutes (AHRM), a weighted load metric that respects both how long and how hard you trained. AHRM is the common currency across every screen: your zone calculator, your weekly load tracker, your VO2 max projection, and your training plan all speak the same language.

Open ZoneLab and you know three things at a glance: what zone to train in today, how much AHRM you've accumulated this week, and how that maps to your VO2 max trajectory.

HOW IT WORKS

Most adaptation happens at the extremes. Zone 2 — easy enough to hold a conversation — builds your aerobic engine: mitochondria multiply, fat oxidation improves, cardiac output grows, all without meaningful recovery cost. Zone 4, just below threshold, stresses that engine into adapting further. ZoneLab targets the balance that works: roughly 80% easy, 20% hard.

FREE, AND GENUINELY USEFUL

• Five-zone heart rate calculator (Karvonen method — max HR and resting HR)
• AHRM weekly load tracker
• VO2 max estimator — Cooper test, Rockport walk, Uth-Sørensen-Overgaard-Pedersen formula, and race-result calibration
• VO2 max projection chart, with saved baseline markers so you can track how your trajectory shifts over time
• Manual zone-minute logging

The free tier isn't a trial. It's a complete, useful tool on its own.

GO DEEPER, IF YOU WANT TO

Sync — automatic import of workouts from Apple Health, so your AHRM updates itself as you train, with no manual entry. Sync is an auto-renewing subscription, billed monthly or yearly after a 14-day free trial; cancel anytime in your Apple ID subscription settings.

Progression — a full periodised training plan: phase-aware AHRM targets, deload weeks built in, and a session optimizer that fits your week to your VO2 max goal. One-time purchase.

Race Prep — a race-day physiology calculator, primarily for runners. Heart-rate profiling, pace prediction, lactate-threshold modelling, cardiac drift, and nutrition planning, all derived from physiological first principles and tunable against your own race data. One-time purchase.

WHO IT'S FOR

Recreational endurance athletes — runners, cyclists, swimmers, rowers — who've heard of Zone 2, care about long-term aerobic health as much as short-term performance, and want their training data to mean something rather than just accumulate.

No coaching upsell. No social feed, no leaderboards. No hardware required — the free tier works with nothing but a phone and a stopwatch.

ZoneLab is a fitness and training tool, not a medical device. It doesn't diagnose, treat, or replace advice from a physician — consult one before starting a new exercise programme, especially if you have a cardiovascular, respiratory, or metabolic condition.

Forever in motion.

Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/