Above the anaerobic threshold, lactate builds up faster than your body can clear it and fatigue comes quickly. Training just below it improves endurance; knowing it helps you pace races.
How to use the Anaerobic Threshold Calculator
- Age (years)
- Maximum heart rate formula
- Measured maximum heart rate (bpm)
Results update as you type, every field has its own unit menu, and everything is calculated in your browser.
How it works
Enter your age and choose a formula, or enter a measured maximum heart rate.
Inputs explained
| Field | What to enter |
|---|---|
| Age (years) | A number |
| Maximum heart rate formula | Choose one: Fox – 220 − age, Tanaka – 208 − 0.7 × age, Nes – 211 − 0.64 × age, Inbar – 205.8 − 0.685 × age … |
| Measured maximum heart rate (bpm) | A number |
What each result means
- Anaerobic threshold = round(0.85×[Maximum heart rate])
- Threshold range from = round(0.80×[Maximum heart rate])
- Threshold range up to = round(0.90×[Maximum heart rate])
Example values
How the main result changes when Age changes and everything else stays at the example values above:
| Age (years) | Anaerobic threshold (bpm) |
|---|---|
| 17.5 | 166 |
| 26.25 | 161 |
| 35 | 156 |
| 43.75 | 151 |
| 52.5 | 146 |
| 70 | 135 |
Formula
AT ≈ 0.85 × HRmax (range 0.80–0.90 × HRmax) · HRmax from Fox, Tanaka, Nes, Inbar, Gellish or Gulati
Worked example
Inputs — Age (years): 35; Maximum heart rate formula: Tanaka – 208 − 0.7 × age.
Results — Maximum heart rate = 184 bpm; Anaerobic threshold = 156 bpm; Threshold range from = 147 bpm; Threshold range up to = 165 bpm.
Key terms
- Lactate
- By-product of fast energy production.
Frequently asked questions
What is the anaerobic threshold?
The intensity above which lactate accumulates quickly.
Is it the same as lactate threshold?
Very close – the terms are often used interchangeably.
How can I measure it accurately?
A lab lactate test or a 30-minute time trial.
Can I raise my threshold?
Yes – tempo and threshold training raise it considerably.