by Matt Fitzgerald and David Warden
For details on determining LTHR, TP, CV, and FTP please see Intensity Guidelines for Triathlon and Running. If you have a TrainingPeaks account, the 80/20 Zones can be auto-calculated directly within TrainingPeaks. Please see Understanding your TrainingPeaks Structured Workout Plan for more information. However, you do not need an 80/20 training plan nor TrainingPeaks account to utilize the calculator. For best results, frequent users of this calculator should clear browser cache to ensure the latest calculations have been loaded. Use the Reset button below to reset values.