What is calculated
The age-group midpoint associated with the nearest FRIEND mean VO2max.
Cardiorespiratory Fitness Age Comparison
Closest FRIEND age midpoint
Enter your values, then calculate to see a verified result.
Reference range
How this result is calculated
A clear calculation path based on your inputs.
Inputs usedReview the information used for this result.
Full calculation and sourcesOpen Full calculation and sources to review the method, assumptions, boundaries, and evidence.
Versioned calculationFormula v1.0.0
Method
Use sex-specific published means and the midpoints between adjacent means.
Important boundary
The result does not turn a fitness measure into literal age.
Enter a defensible VO2maxUse the labeled field and matching unit.
Compare with FRIEND meansThe calculator applies the displayed method at full precision.
Keep it as a referenceKeep the stated boundary beside the result.
Interpretation
The primary value names a reference-group midpoint.
The signed difference keeps chronological age visible.
Do not interpret the result as years added to or removed from life.
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Method and test recordFormula v1.0.0
- Recorded scope
- health-evidence-completion
- Publisher
- CalculatorGeek
- Recorded review date
- 2026-10-05
- Next source review
- 2027-04-05
- Definition fixtures
- 2 configured scenarios
- Published examples
- 2 shown below
Recorded method
Verify all FRIEND means, adjacent midpoint boundaries, both sex tables, and age-range handling.
These records describe the published model and reference tests. A test-case count is not a certification of every possible input or an independent specialist review. Editorial policy
Known limitations
- Uses group means, not percentiles.
- Test protocol, equipment, effort, altitude, health, and training affect VO2max.
- Reference table is sex-specific and limited to ages 20-79.
- Not biological age or mortality risk.
Method sources
Latest model update
2026-10-05 - Initial evidence-limited shared-system implementation with fixtures, original support content, and contextual links.
Reference inputs and expected results
Up to 12 examples from the configured definition fixtures are shown. Expected values use the stated output units; invalid inputs are intended to be rejected.
| Case | Inputs | Expected result |
|---|---|---|
| male forty year reference fixture | FRIEND reference table: male; Chronological age: 45 years; Measured or separately estimated VO2max: 38 number | Closest FRIEND age-group midpoint: 44.5 years; Reference midpoint minus chronological age: -0.5 years; classification: similar-reference-group (allowed numeric tolerance: 0.0001) |
| female high reference fixture | FRIEND reference table: female; Chronological age: 55 years; Measured or separately estimated VO2max: 36 number | Closest FRIEND age-group midpoint: 24.5 years; Reference midpoint minus chronological age: -30.5 years; classification: younger-reference-group (allowed numeric tolerance: 0.0001) |
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On this page
What the Cardiorespiratory Fitness Age Comparison calculates
Compare an entered VO2max with published FRIEND age-group means and report the closest reference midpoint.
The route provides a transparent comparison instead of inventing a multi-factor fitness-age algorithm.
Start with the Health calculators hub when a neighboring workflow better matches the question.
How to use the Cardiorespiratory Fitness Age Comparison
- Obtain VO2max from an appropriate test or separate estimator.
- Select the matching reference table.
- Enter chronological age.
- Read the closest reference group, not a literal biological age.
Continue with the VO2 Max Calculator. Estimate or interpret aerobic capacity.
Formula, variables and calculation order
Published mean VO2max values are compared with midpoint boundaries between adjacent 10-year age groups.
Inputs are validated and normalized before the calculation. Working precision is retained until display rounding.
For a separate method, open the Heart Rate Zone Calculator. Set training zones from heart-rate inputs.
Worked example and boundary check
Worked example
A male VO2max of 38 mL/kg/min maps closest to the 40-49 FRIEND mean of 38.8, reported as midpoint 44.5.
Boundary check
A value exactly on a midpoint boundary is assigned to the younger/higher-fitness adjacent group by the displayed rule.
How to interpret the result
The comparison can contextualize aerobic capacity but does not explain why a value is high or low.
- Uses group means, not percentiles.
- Test protocol, equipment, effort, altitude, health, and training affect VO2max.
- Reference table is sex-specific and limited to ages 20-79.
- Not biological age or mortality risk.
Compare the result with the One Rep Max Calculator. Estimate maximal strength from a submaximal set.
Frequently asked questions
Is this my biological age?
No.
Why use age-group midpoints?
The source reports 10-year groups rather than a continuous age equation.
Can I enter a watch estimate?
You can compare it, but device error remains part of the result.
Does a younger group mean lower health risk?
The calculator does not make that inference.
Primary sources and evidence limits
Sources and version-sensitive boundaries were checked 2026-10-05. The page does not replace diagnosis, prescribing, emergency care, or individualized professional judgment.