Home / Biological Clocks & Cellular Aging / Fitness Age / Physical form

Aerobic fitness · Level 2

Physical form age: your VO₂max

How young is your cardiorespiratory system working? The key metric is VO₂max, your maximum oxygen uptake. From it, your resting heart rate and your activity level, the calculator estimates the age of your form, your maximum heart rate, heart rate reserve and personal heart rate zones.

VO₂maxat the core 0lab tests ~2 minto calculate 5heart rate zones

VO₂max

the “gold standard” of aerobic fitness and a predictor of longevity

5–10%

the drop in VO₂max per decade after age 30 without training

8–12 wk

until a noticeable rise in VO₂max with regular training

personal heart rate zones based on your maximum heart rate

Method

How physical form age is calculated

From your age we estimate your maximum heart rate (the Tanaka formula), and from that, your resting heart rate and an activity adjustment — your VO₂max. It is then compared with the typical VO₂max for your sex and age: however far above or below the norm you are, that is how many years your form is “younger” or “older” than your calendar age.

01

favorite

Heart rate and age

Resting heart rate and age set your maximum heart rate and heart reserve.
arrow_forward
02

directions_run

Activity

Your activity level refines the VO₂max estimate — your aerobic power.
arrow_forward
03

monitor_heart

VO₂max

Comparison with the norm by sex and age gives your form age.
arrow_forward
04

insights

Form and zones

Your form age, heart rate zones and steps to improve.

Physical form age calculator

Sex, age and resting heart rate are required. Height and weight are optional (for BMI). The key is an accurate resting heart rate: measure it in the morning, right after waking, lying down, over 60 seconds.

1Basic data

Nameoptional

Sex

Chronological age18–90

years

Resting heart rate30–120

bpm

Heightoptional

Weightoptional

info

Resting heart rate is the main input. Measure it in the morning, lying down, before coffee or exercise; the average nighttime value from a fitness tracker works too.

2Activity

Activity level

Main type of training

Physical form age

— years

The age of your aerobic fitness

—

Form vs. your calendar age

−15 (younger)−30+3+15 (older)

Cardiorespiratory metrics

VO₂max (estimate)

— ml/kg/min

—

Maximum heart rate

— bpm

Estimated with the Tanaka formula.

Heart rate reserve

— bpm

The gap between rest and maximum.

BMI

—

For context.

Your VO₂max vs. an elite benchmark — of 70 ml/kg/min

0averagegood🏆 70+ elite

Your personal heart rate zones

lightbulb

How to improve your form age

Personal steps for your level. This is educational information, not a substitute for a doctor's consultation.

info

VO₂max and form age are a rough estimate from resting heart rate and activity, not a laboratory gas analysis. Before a noticeable increase in training load, especially with heart disease or high blood pressure, consult a doctor.

For information only — not medical advice; consult a qualified healthcare provider before making any health decision. The values you enter are used only to calculate your result and are not stored on our servers.

What VO₂max is and why it matters most

VO₂max is the maximum volume of oxygen the body can take up per minute at peak effort (ml/kg/min). It is the “gold standard” of aerobic fitness and one of the strongest predictors of life expectancy. To see it alongside strength, flexibility and habits, try fitness age across six factors.

A runner's silhouette with a heart rate graph — aerobic fitness and VO₂max — Regular aerobic exercise raises VO₂max through a stronger heart, a denser network of capillaries and more efficient muscles.

Heart rate zones: protecting the heart

Zones are calculated from your maximum heart rate and set your training intensity. For health and longevity the aerobic base (Zone 2) is especially valuable — 80% of your volume is worth keeping there, since it is what lowers cardiovascular risk.

Resting heart rate and fitness level

The lower your resting heart rate, the more efficiently your heart works. It is one of the most accessible markers of fitness — easy to track at home.