Blog
LTHR articles
7 articles on LTHR, newest first. Every one is sourced and links to the calculator it applies to.
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 to Find Your Lactate Threshold
What lactate threshold is (LT1 vs LT2), why it anchors your zones, and how to find it: a 30-minute LTHR field test, race or power methods, or a lab test.
Friel's Heart-Rate Zones: 5, 7, and Why Every Platform Numbers Them Differently
Joe Friel's LTHR zones explained: the 5-zone model, the 5a/5b/5c split that makes it 7, how intervals.icu renumbers them, and how to test your LTHR.
What Heart Rate Zone Should You Train In?
Which heart-rate zone to train in and when: most time easy in Zone 2, a controlled dose at threshold, a little in Zone 5. Plus how to find your zones.
LT1, LT2, and LTHR: The Lactate Thresholds Explained
What LT1, LT2 and LTHR mean, where they sit on the lactate curve, and how aerobic threshold, anaerobic threshold, OBLA, MLSS and VT1/VT2 map onto them.
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.
How Quentin Fillon Maillet Trains (Eight Olympic Medals, Every Format)
France's most decorated Olympian has medalled in every biathlon format, from a 23-minute sprint to a 50-minute individual. That range is a threshold story.