O2 Max Chart by Age and Fitness Level: How to Read Your Number

VO2 max is one of the most widely used measures of cardiorespiratory fitness. It describes the highest rate at which your body can take in, transport, and use oxygen during intense aerobic exercise.

The number becomes useful only after you add context.

A VO2 max of 35 mL/kg/min can sit near the median for one age and sex group while ranking well above the median for another. Interpretation also changes depending on whether the result came from laboratory testing, a field test, or a wearable estimate.

This guide provides age- and sex-based reference percentiles and explains how to read your number without treating one chart or one wearable result as a universal fitness grade.

Quick Answer: What Is a Good VO2 Max?

A good VO2 max is a result that compares favorably with an appropriate reference group and supports your personal health or performance goals.

Use four questions:

1. Was the value measured directly or estimated?
2. Which age and sex reference group applies?
3. Was the test performed on a treadmill or cycle ergometer?
4. Is the value improving, stable, or declining over time?

Percentiles provide clearer context than labels such as “good” or “excellent,” because those labels vary between charts.

Percentile Position	Practical Interpretation
Below 25th	Lower quartile of the matching reference group
25th–49th	Below the group median
Around 50th	Near the group median
50th–74th	Above the group median
75th–94th	High relative cardiorespiratory fitness
95th or higher	Very high relative to the reference group

These percentiles describe population position. They are not diagnostic thresholds or mandatory fitness targets.

VO2 Max Chart for Men by Age

The table below uses updated U.S. treadmill cardiopulmonary exercise testing reference values. All numbers are in mL/kg/min.

Age	25th Percentile	50th Percentile	75th Percentile	95th Percentile
20–29	37.3	45.4	52.6	62.1
30–39	31.3	38.6	46.5	57.9
40–49	28.4	34.8	41.8	53.2
50–59	23.9	29.4	35.5	46.8
60–69	19.7	24.4	29.9	40.2
70–79	16.8	20.6	25.0	35.2
80–89	15.9	17.7	20.9	25.6

VO2 Max Chart for Women by Age

Age	25th Percentile	50th Percentile	75th Percentile	95th Percentile
20–29	28.6	35.6	42.2	50.1
30–39	23.1	28.3	34.5	45.5
40–49	21.3	25.9	30.9	40.7
50–59	19.5	23.1	27.3	35.3
60–69	16.4	19.4	23.1	29.7
70–79	14.8	17.1	20.0	24.2
80–89	12.8	15.1	17.2	20.7

Reference note: These are directly measured treadmill CPET percentiles from apparently healthy U.S. adults. The original dataset used male and female categories. Results from other populations, test protocols, and exercise modes may differ.

How to Read Your VO2 Max Number

Start with your age row and the sex category used by the reference dataset.

Suppose a 45-year-old man has a directly measured treadmill VO2 value of:

35 mL/kg/min

For men aged 40–49, the updated reference median is 34.8. The result is therefore close to the 50th percentile.

Now consider the same value for a 45-year-old woman.

For women aged 40–49, 35 falls above the 75th-percentile value of 30.9 and below the 95th-percentile value of 40.7.

The number stayed the same. Its population context changed.

What Does mL/kg/min Mean?

Relative VO2 max is usually expressed as:

milliliters of oxygen per kilogram of body mass per minute

This allows oxygen use to be interpreted relative to body size.

Laboratories can also report absolute oxygen consumption in liters per minute. Relative and absolute values answer related but different questions.

Metric	Unit	What It Describes
Absolute oxygen uptake	L/min	Total oxygen used per minute
Relative oxygen uptake	mL/kg/min	Oxygen use adjusted for body mass

Why Body Weight Can Change Relative VO2 Max

Body mass is part of the relative VO2 calculation.

If body weight decreases while absolute oxygen-consuming capacity remains similar, the relative value in mL/kg/min can rise.

If body weight increases, the relative value can fall even when absolute oxygen uptake changes less.

When interpreting a long-term trend, review both training changes and meaningful changes in body mass.

Why VO2 Max Changes With Age

Population VO2 max values generally decrease across adulthood.

Contributors can include changes in:

• maximum heart rate
• cardiac output
• muscle mass and oxygen use
• physical activity
• training consistency

The chart describes population trends. Regular aerobic training can help maintain much higher cardiorespiratory fitness than an inactive lifestyle at the same age.

For a broader explanation of the physiology, see how cardiovascular capacity relates to VO2 max and endurance.

Laboratory Test vs Field Test vs Wearable Estimate

Method	How It Works	Best Use
Laboratory CPET	Measures respiratory gases during progressively harder exercise	Direct aerobic-capacity assessment
Field test	Uses distance, time, heart rate, or recovery in a prediction equation	Accessible fitness estimate
Wearable estimate	Uses an algorithm based on exercise, heart rate, pace, activity, and profile data	Convenient repeated trend tracking

A laboratory CPET directly measures oxygen and carbon-dioxide exchange while workload increases.

A wearable estimates aerobic capacity from indirect inputs. The displayed result can be useful while remaining method-dependent.

Why Wearable VO2 Max Can Differ From a Lab Test

A wearable estimate can be affected by:

• heart-rate signal quality
• pace or distance accuracy
• hills and terrain
• heat and humidity
• fatigue or illness
• incorrect age, weight, or profile information
• estimated maximum heart rate
• the algorithm's training population

Two platforms can also use different algorithms and produce different values from similar exercise data.

Use one system consistently when following a trend.

Low Average Bias Does Not Guarantee Individual Accuracy

A wearable algorithm can perform well across a group while still producing a meaningful error for an individual.

Positive and negative errors can cancel each other when researchers calculate the group average.

This means a wearable value may place you in a different percentile band from a directly measured result.

Use wearable VO2 max primarily to answer:

“Is my estimate moving consistently over several weeks or months?”

Do Not Compare Treadmill and Cycling Results Directly

The tables in this article use treadmill CPET reference values.

Cycle-ergometer testing can produce a different result because it uses a different movement pattern, active muscle mass, and exercise-specific training background.

Use:

treadmill result → treadmill reference

and:

cycle result → cycle reference.

A trained cyclist may also perform differently from someone who primarily runs.

VO2 Max and Endurance Are Related but Different

VO2 max describes maximal aerobic capacity.

Endurance performance also depends on:

• exercise economy
• lactate or ventilatory threshold
• pacing
• muscular endurance
• fueling and hydration
• training experience

Two runners with similar VO2 max values can therefore produce different race times.

How to Use Your Number Over Time

A practical interpretation sequence is:

Measure → Match the Reference → Check the Method → Track the Trend

1. Measure

Identify whether the value came from laboratory testing, a field test, or a wearable.

2. Match the Reference

Use the appropriate age, sex, and exercise-mode reference.

3. Check the Method

Avoid treating estimates and direct measurements as interchangeable.

4. Track the Trend

Compare repeated results collected with the same system and broadly similar conditions.

The RingConn baseline guide explains why repeated personal data is more informative than isolated measurements.

How Can You Improve VO2 Max?

Cardiorespiratory fitness responds to consistent aerobic training.

A balanced program can include:

• sustainable low-to-moderate aerobic volume
• appropriately programmed higher-intensity intervals
• gradual increases in training load
• adequate sleep and recovery

Lower-intensity work supports training consistency and aerobic volume. Higher-intensity work provides a more direct stimulus near maximal aerobic demand.

Use our heart rate zones guide and Zone 2 vs. Zone 3 comparison to understand how intensity changes the training stimulus and recovery cost.

How RingConn Fits Into VO2 Max Tracking

RingConn's current product comparison lists VO2 max functionality across the current ring lineup.

The available experience can depend on the current model, App version, workout data, and supported configuration.

RingConn VO2 max information should be treated as a wellness and fitness estimate unless the value comes from a directly measured laboratory result.

Its strongest use is combining the VO2 max trend with broader context such as:

• heart rate
• activity
• sleep
• HRV
• recovery patterns

Check the current RingConn product comparison for model-specific feature availability.

When Is Laboratory Testing Worth Considering?

A supervised laboratory test can be useful when you:

• need a precise performance baseline
• want to verify a wearable estimate
• are planning structured endurance training
• need exercise testing under professional supervision
• have unexplained exercise intolerance and a clinician recommends testing

Seek appropriate medical evaluation for chest pain, fainting, severe dizziness, significant unexplained shortness of breath, or a major unexplained decline in exercise capacity.

Final Takeaway

A VO2 max number needs four types of context:

Measurement Method + Age and Sex Percentile + Exercise Mode + Personal Trend

The updated treadmill reference tables show that expected values generally decline with age and differ between the male and female categories used by the dataset.

Percentiles are more transparent than universal “good” or “excellent” labels. They tell you where a directly measured result sits within a matching reference group.

Laboratory CPET directly measures respiratory gases during progressively demanding exercise. Wearables estimate aerobic capacity from indirect signals and are especially useful for repeated trend tracking.

Use the same device or testing method, compare similar conditions, and give multi-week changes more weight than one isolated estimate.

RingConn products are intended for personal health, fitness, and wellness awareness and are not medical devices. VO2 max estimates, heart rate, HRV, activity, sleep, and other RingConn wellness information should not replace cardiopulmonary exercise testing, professional medical advice, diagnosis, emergency assessment, or treatment.

FAQ: VO2 Max by Age and Fitness Level

What is a good VO2 max for my age?

Compare your result with the matching age-, sex-, and test-specific percentile table. A result near the 50th percentile is around the group median, while the 75th percentile or higher indicates relatively high cardiorespiratory fitness within that reference group.

Is a VO2 max of 40 good?

It depends on age, sex, testing method, and exercise mode. A value of 40 can sit below the median for a young male reference group while ranking well above the median for many older or female reference groups.

How accurate is wearable VO2 max?

Accuracy varies by device, algorithm, fitness level, workout type, and sensor data. Exercise-based algorithms often perform better than models relying mainly on resting information, but individual estimates can still differ materially from laboratory results.

Is laboratory VO2 max more accurate than a wearable estimate?

Laboratory CPET directly measures oxygen and carbon-dioxide exchange during progressive exercise. A wearable uses indirect inputs to estimate aerobic capacity, making laboratory testing the stronger method when precise measurement is required.

Can I compare a cycling VO2 max with this chart?

The chart in this article uses treadmill reference values. Cycling results should be interpreted with cycle-specific standards because exercise mode can materially change the measured value.

Why did my VO2 max change after my weight changed?

Relative VO2 max is divided by body mass. A change in weight can therefore alter the mL/kg/min result even when absolute oxygen-consuming capacity changes less.

How often should I check VO2 max?

Wearable estimates can be reviewed as a multi-week or monthly trend. Laboratory testing is usually repeated less frequently and should use a comparable protocol when tracking change.