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LTHR Estimator | Sports Calculator
LTHR Estimator - Lactate threshold HR from 30-min time trial: LTHR = avg HR of last 20 minutes
Built by an engineer who chases finish lines and is obsessed with data. Thomas Prommer — technology executive who has worked with Google, Apple, Nike, Adidas, Netflix and other global brands. Also an Ironman finisher, HYROX Pro Division competitor, and marathon runner. These tools combine engineering rigor with real race experience.
LTHR Estimator
Lactate threshold HR from 30-min time trial: LTHR = avg HR of last 20 minutes.
Methodology
Lactate threshold HR from 30-min time trial: LTHR = avg HR of last 20 minutes. Alternative: 85-90% of max HR. Used for zone-based training.
FAQ
How does this calculator work?
Lactate threshold HR from 30-min time trial: LTHR = avg HR of last 20 minutes. Alternative: 85-90% of max HR. Used for zone-based training.
How accurate is this?
Based on established sports science formulas and research.
Who should use this?
Athletes, coaches, and fitness enthusiasts of all levels.
Should I consult a professional?
Yes, especially before major changes to training or for health conditions.
Results are estimates. Consult a professional for personalized guidance.