Can agents run this deterministically?

Yes. Supply method, age, gender, weight, and test-specific inputs as JSON to receive vo2max, classification, and fitness_age deterministically.

Cardio

VO2 Max Estimator

Estimate your VO₂ max aerobic capacity using the Cooper run test, Rockport walk test, or a no-exercise questionnaire.

Your VO₂ Max

90.6ml/kg/min

Superior

VO₂ Max Position

Your estimate is plotted against broad aerobic fitness bands.

VO₂ max (ml/kg/min)

Superior

90.6

15100

Estimated Fitness Age

15 years

Method: Non-Exercise Estimation (Nes et al.)

Formula: VO₂max = 100.27 + 7.17×PA − 0.164×wt − 0.39×age − 18.07×sex

⚠️ Field-test estimates are approximations. Lab-grade VO₂ max testing (gas exchange analysis) is the gold standard. Consult a healthcare professional before starting any new exercise program.

How to use it

Use the Cooper Test (maximum distance covered in 12 minutes) or your best recent 1.5-mile time for accurate input. The estimate is only as reliable as the effort — a hard but comfortable 12-minute effort (not all-out sprint) gives the best result.
VO2 max age-group norms (mL/kg/min) — Men: 20s: 42+ good, 38–42 average; 40s: 35+ good. Women: subtract 6–8 points from each benchmark. Above 50 is excellent at any age.
VO2 max is highly trainable: 8–12 weeks of consistent Zone 4–5 interval training (3–5 minute hard intervals at near-maximal effort) improves VO2 max by 5–15% in untrained and intermediate individuals.
A higher VO2 max means you can sustain a faster pace at a lower percentage of maximum effort — this simultaneously improves speed at all distances and improves endurance fatigue resistance.
Retest every 8–12 weeks. Meaningful gains require consistent cardiovascular training (3+ sessions/week). A 2–4 point VO2 max increase over a 12-week block represents strong aerobic development.

AI Integrations

Contract, discovery endpoints, and developer notes for agent use.

Always available for agents

Tool contract JSON

https://aifithub.io/contracts/vo2-max-estimator.json

Stable input and output contract for this exact tool.

Human review

People can use the browser page to sense-check outputs and charts, but agents should still execute against the contract and discovery endpoints.

/agent-tools.json - machine-readable tool index.
/llms.txt - human-readable model discovery guide.
/.well-known/webmcp.json - WebMCP capabilities manifest.
/.well-known/ai-plugin.json - plugin-style discovery manifest.

{
  "tool": "vo2_max",
  "method": "questionnaire",
  "age": 30,
  "gender": "male",
  "weight_kg": 75,
  "activity_level": "moderate"
}

Open tool contract JSON Open AI integrations guide

Expand developer notes

Agent playbook

Resolve VO2 Max Estimator from /agent-tools.json and open its contract before execution.
Validate inputs against the contract schema instead of scraping labels from the page UI.
Open the browser page only when a person wants to review charts, assumptions, or related tools.

Agent FAQ

Should ChatGPT, Claude, or another agent click through the UI?

No. Start with /agent-tools.json, then follow the tool's contract URL. The page UI is for human review, not parameter discovery.

When do tools show Quick and Advanced?

Every tool opens in Quick Start first. Advanced Controls keeps the same scenario, reveals more assumptions or diagnostics, and every tool keeps AI integrations inline below the instructions.

When should an agent still open the browser page?

Open it when a human wants to sense-check the output, review the chart, or keep exploring related tools after the calculation finishes.

Questions people usually ask

Which estimation methods are available?

Three validated methods: Cooper 12-minute run test, Rockport 1-mile walk test, and a no-exercise questionnaire based on the Nes et al. (2011) regression model.

How accurate are field-test VO₂ max estimates?

Field tests typically correlate 0.85–0.95 with lab-grade gas exchange testing. They are useful for tracking trends but not as precise as clinical measurement.

What is a good VO₂ max score?

For males: 40–50 ml/kg/min is Good to Excellent. For females: 35–45 ml/kg/min. Elite endurance athletes can exceed 70 ml/kg/min.

What is fitness age?

Fitness age estimates your biological age based on aerobic capacity compared to population norms. A 50-year-old with superior VO₂ max may have a fitness age of 35.

Is this tool free and private to use?

Yes. AI Fit Hub tools are free, no-signup browser tools. Inputs stay in your browser unless you choose to share a URL.

Related Resources

Learn the decision before you act

Every link here is tied directly to VO2 Max Estimator. Use the explanation, formula, examples, and benchmarks to pressure-test the calculator output from first principles.

Browse all 36 resources

Guides · 1 Checklists · 1 Comparisons · 1 Learn · 2 Tips · 5

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