ExplainerFitness & Body Composition

What is a good VO2 max?

VO2 max is how well your body uses oxygen when you push hard. It is closely linked to how long and how well you age.

Agnes Wong, Nutritionist · SNDA Accredited Medically reviewed by Dr Edith Loo
Published 21 August 20261 min read

What is VO2 max?

VO2 max is the most oxygen your body can use during hard exercise. The fitter you are, the more you can use.

It reflects your heart, lungs, capillaries, red blood cells, nerves, muscles and mitochondria working together. It is a whole system measure, not a reading from one organ.

Think of it as the size of your engine. A bigger engine handles more, and it does so with less strain. You feel it in ordinary life, not just in sport. A bigger engine makes a flight of stairs feel like nothing.

Why it matters

A higher VO2 max tracks with a longer, healthier life. It is one of the strongest signals of future health we can measure.

It tends to fall with age, and that is normal. What is not fixed is how fast.

IT FALLS EITHER WAY. TRAINING CHANGES HOW FAST.
VO2 max drops around ten percent a decade after 30 if you do nothing.
50403020
20304050607080
AgeVO2 max, ml/kg/min
Kept trainingDid nothing
The gap at 80 is roughly the difference between climbing your own stairs and not.

That gap is the whole argument for paying attention to it. Training does not stop the decline, it flattens it.

What counts as good?

Good depends on your age, sex, and your body size, because VO2 max is usually reported per kilogram. Compare yourself to your own group, not to an athlete on television.

You do not need an elite number. The jump from the lowest band to average brings the biggest gain in health. Move up one band for your age, then hold it.

How to raise it

01
Build an easy base
Regular cardio at a pace where you can still hold a conversation. This is where most of the gain actually comes from.
02
Add a little hard work
One or two short, genuinely hard efforts a week lift the ceiling. Easy days in between to recover.
03
Be consistent, not heroic
Three or four sessions a week, kept up over months, moves the number. Intensity every session does not.
04
Pick something you will keep doing
A brisk walk, a cycle or a swim all count. The best plan is the one you do not dread.

How it fits with muscle

Cardio fitness and muscle are a pair, not rivals. Muscle carries you, and a strong heart and lungs power it.

Looking after both is what keeps you steady and independent later. That independence is the real goal behind the number.

How to measure it

A lab test on a treadmill or bike is the most exact. A smartwatch estimate is rougher, but useful for tracking your own trend.

Do not read too much into a single watch reading. It is the direction over months that tells the story.

Where to start

If you do little now, start with easy walks you can sustain, and build the habit before you build the intensity. Add a little more each week, in time or in effort.

The two traps

The first is going hard every session. It leaves you tired, sore and more likely to stop, and it crowds out the easy work that produces most of the gain.

The second is treating rest as time off. Easy days and decent sleep are when the adaptation actually happens, which makes them part of the training rather than a break from it. If every session leaves you wiped out, ease off.

If you have a heart condition

Check with your doctor before starting hard efforts. This matters if you have a heart or lung condition.

Start gentle and build slowly with guidance. Safe, steady progress beats fast progress every time.

The bottom line

The number matters less than the direction it is moving. Most people are not trying to become athletes. They are trying to still be climbing their own stairs at eighty.

That is within reach from almost any starting point, and it is the reason this is worth measuring at all.

Agnes Wong
Nutritionist · SNDA Accredited
Agnes turns a set of results into something a person can actually do on a Tuesday. She works with members on nutrition, training and the habits that hold, and writes the parts of this publication that have to survive contact with real life.
Medically reviewed by Dr Edith Loo, Lead Clinician, on 21 August 2026. General health information, not medical advice, and not a substitute for consultation with your own doctor.
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