Threshold Heart Rate Calculator - Bike
What is Threshold Heart Rate (ThHR)?
Threshold heart rate is the heart rate at which blood lactate begins to accumulate faster than it can be removed, marking the highest steady‑state intensity you can sustain for roughly 60 minutes. It closely reflects your maximal aerobic endurance and provides a reliable marker for endurance training.
Why measure your ThHR?
Structuring sessions around % of ThHR ensures each workout targets the intended physiological stress: efforts below ThHR develop aerobic capacity without undue fatigue, while efforts at or above ThHR enhance lactate clearance and high‑intensity tolerance.
Performing your 20‑Minute HR Threshold Test
Warm‑up (15–20 min): easy spinning with a few short accelerations.
20 min maximal effort: ride at the highest steady power you can maintain on flat terrain or a smart trainer.
Cool‑down (10 min): easy pedalling.
Your average heart rate over the full 20 min is your ThHR.
Extracting your Average ThHR
On your head unit: start and stop a lap at the beginning and end of your 20 min test, then view the lap’s average HR.
In TrainingPeaks: upload your ride, create a 20 min custom split, and inspect the Average Heart Rate in the split summary.