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heart rate zones articles
15 articles on heart rate zones, newest first. Every one is sourced and links to the calculator it applies to.
How Matthew Marquardt Trains (Kona Podium on 20 to 25 Hours a Week)
Matthew Marquardt finished third at Kona 2026 while still in medical school. His coach steers every session by lactate threshold, not by power or pace.
How Julie Derron Trains (and Why She Runs Without a Watch)
Julie Derron took third at Kona 2026 on her debut, running the marathon without a watch. How Brett Sutton's athlete races by feel, and how to learn it.
How Fitbit Calculates Your Max Heart Rate (HRmax)
Fitbit estimates HRmax with 220 − age, then personalises your zones using heart rate reserve. That second step is why its zones look wrong to runners.
How Every Watch Calculates Your Max Heart Rate (10 Brands Compared)
Garmin uses Tanaka, COROS uses Gellish, Apple publishes nothing, Wahoo skips HRmax entirely. Ten brands, their formulas and zone models, in one table.
How Garmin Calculates Your Max Heart Rate (HRmax)
Garmin estimates HRmax from your age (208 − 0.7 × age), then raises it from new peaks. How auto-detection works, what it drives, and how to set it.
How WHOOP Calculates Your Max Heart Rate (HRmax)
WHOOP starts with the Gellish formula, then adjusts your max heart rate from 24/7 data. It is the only major brand that says it learns the number.
How COROS Calculates Your Max Heart Rate (HRmax)
COROS recommends 207 − 0.7 × age for HRmax, offers three zone models, and analyses your training with lactate-threshold zones whichever one you pick.
How Apple Watch Calculates Your Max Heart Rate (HRmax)
Apple never publishes the formula. What Apple does say about HRmax and zones, what the community has reverse-engineered, and how to override it.
How Strava Calculates Your Heart Rate Zones
Strava uses 220 − age, falls back to 190 bpm with no age on file, and silently rewrites your zones on your birthday. Here is how to take control.
How Wahoo Calculates Your Heart Rate Zones (THR, not HRmax)
Wahoo is the one brand that builds zones from threshold heart rate rather than maximum. It seeds THR at 88% of a Tanaka estimate. Here is how to fix it.
How Samsung Galaxy Watch Calculates Your Max Heart Rate
Samsung starts at 220 − age, now layers Galaxy AI personal zones on top, and keeps the setting per exercise type rather than once for everything.
Why Your LTHR Zone 2 Is Higher Than Your %HRmax Zone 2
Switched your watch to LTHR zones and Zone 2 jumped 20–30 beats? Nothing is broken. Why %HRmax and LTHR zones differ and why Zone 2 means three things.
Rowing UT2: What It Is and Why It Builds Your Engine
UT2 is rowing's easy aerobic base band. What it means, the heart rate and stroke rate to hold, how it fits the UT2–AN system, and how to row it well.
How Suunto Calculates Your Max Heart Rate (HRmax)
Suunto defaults to 220 − age and then draws unusually narrow zones on top of it, which is why the same run lands in a different zone than on a Polar.
How Polar Calculates Your Max Heart Rate (HRmax)
Polar still defaults to 220 − age and draws five zones as clean 10-point bands of it. What that costs you, and how to replace it per sport.