Anaerobic Threshold Calculator
Estimate your anaerobic (lactate) threshold heart rate from age and resting heart rate — the intensity at which lactate accumulates faster than your body can clear it.
Reviewed October 7, 2026 Runs in your browser — inputs are never stored
This tool provides general sports and fitness estimates for educational purposes only. It is not medical advice — consult a physician before starting or intensifying training, especially if you have a cardiovascular condition.
About the Anaerobic Threshold Calculator
The anaerobic threshold calculator estimates the heart rate above which lactate builds up faster than the body can clear it. It uses 85% of heart-rate reserve added to resting heart rate, with maximum heart rate estimated as 220 − age. Training near threshold improves the pace you can sustain in races; a lab or field test gives a more precise value.
How to use it
- 1Enter your age.
- 2Enter your resting heart rate.
- 3Press Calculate.
Worked example
a 34-year-old with a resting heart rate of 58 has an estimated maximum of 186 bpm and a threshold of about 58 + 0.85 × 128 ≈ 167 bpm.
How it works
Formula
Threshold HR = Resting HR + 0.85 × (Max HR − Resting HR), with Max HR = 220 − Age.
Example
Age 34, resting 58 bpm: Max HR = 186, HRR = 128, threshold ≈ 58 + 108.8 = 167 bpm.
Common use cases
- Setting tempo-run intensity
- Structuring threshold intervals
- Endurance training plans
Frequently asked questions
A:It is the exercise intensity at which blood lactate rises sharply, usually around 4 mmol/L, corresponding to roughly 85% of heart rate reserve for most trained athletes.
A:Tempo runs or sustained 20–40 minute efforts held at threshold heart rate improve lactate clearance and race pace.
A:Yes — a graded lactate test measures your threshold directly. This estimate is a practical training starting point.
A:Yes — endurance training raises the percentage of VO₂ max you can sustain at threshold.
A:HRR (max HR minus resting HR) personalises zones better than a plain percentage of max heart rate.
Reviewed for accuracy · Last updated October 7, 2026
Formulas follow published sports-science literature and official league definitions (Karvonen heart rate reserve, Cooper and Bruce protocols, MET compendium values, and standard baseball, cricket, and basketball statistics).
CalcWisee Editorial Team
Calculator development and formula review
CalcWisee is an independent site founded by Ayman. Every calculator is built from a published formula or official definition, tested against hand-worked examples before it goes live, and corrected promptly when a reader reports an issue to ayman@calcwisee.com.
Expertise: Financial mathematics, Health and fitness formulas, Applied mathematics, Unit conversion standards
References & sources