ΔέσεWhat is VO₂max and how to improve it
If you wear a sports watch, you've surely seen the "VO₂max" reading. It's one of the most well-known fitness indicators — but what does it actually mean?
What is VO₂max
VO₂max is the maximum amount of oxygen your body can use in one minute of intense exercise. In simple terms, it shows how big the "engine" of your endurance is. The higher your VO₂max, the greater your body's ability to deliver and use oxygen during exercise — so you can run harder for longer.
LungsTake in oxygen from the air
HeartPumps it around with the blood
BloodCarries the oxygen to the muscles
Muscles"Burn" the oxygen for energy
Running performanceFaster • stronger • more endurance
What it depends on
Mainly three things: how much blood your heart sends with each beat, how efficiently your blood carries oxygen, and how well your muscles use it. Genetics play a role too — but the good news is that VO₂max improves with training.
💡 For scale: An average adult has a VO₂max of about 30–45, a fit amateur 50+,
while top endurance athletes reach over 80 (ml/kg/min). Don't compare yourself to the elite —
watch your own progress.
| Level | Women | Men |
|---|---|---|
| Moderate fitness | 30–40 | 35–45 |
| Good fitness | 40–50 | 45–55 |
| Very good | 50–60 | 55–65 |
| Elite athletes | 60+ | 65+ |
Where do you roughly stand?
30Moderate
40Good
50Very good
60Excellent
70+Elite
How to improve it
The most effective way is interval training at high intensity: e.g. repeats of 3–5 minutes near your maximum pace, with rest in between. These push your cardiovascular system to grow stronger.
But be careful: it isn't built with hard days alone. You also need the aerobic base from easy runs, along with a good lactate threshold. It all ties together.
IntervalsVO₂max · ~20% of training
Tempo / Thresholdmoderate intensity
Easy runningaerobic base · 80% of training
❌ Myth: If my VO₂max is low, I can't become a good runner.
✅ Truth: VO₂max is only one factor. Your lactate threshold, running economy and proper training matter just as much.
Your watchEstimate (from heart rate & pace)≈ Estimated VO₂max
Lab testDirect measurement✓ Real VO₂max
Don't fixate on the number. VO₂max is a tool, not the goal. The real aim is to run, improve and enjoy it. 🏃♀️
Frequently asked questions about VO₂max
What is a "good" VO₂max?
There's no single number that applies to everyone — it depends on your age, sex and level. The table above gives rough reference values, but the most useful measure is your own trajectory: if your VO₂max is rising over the months, you're on the right track.
How fast does VO₂max improve?
With consistent training, the first changes usually show up within a few weeks to a few months. Beginners tend to see the biggest improvements — the fitter you get, the slower the extra gains come.
Is the VO₂max on my watch accurate?
It's an estimate based on your heart rate and pace, not a real measurement. Use it to watch your trend over time — not as an exact number.
Does VO₂max decline with age?
Yes, gradually — but consistent aerobic training slows the decline considerably. Runners who keep training often maintain a higher VO₂max than younger, untrained people.
Can I improve it with easy running alone?
At first, yes — any aerobic training helps, especially if you're just starting out. Over time, though, the strongest stimulus is intervals, always built on a solid aerobic base of easy runs.
3 things to remember
- It's the "engine" of your endurance.
- It rises with intervals on an aerobic base.
- Your watch's number is only an estimate.
Sources
The main scientific references behind this article:
- Bassett, D. R., & Howley, E. T. (2000). Limiting factors for maximum oxygen uptake and determinants of endurance performance. Medicine & Science in Sports & Exercise, 32(1), 70–84. PubMed →
- Bacon, A. P., Carter, R. E., Ogle, E. A., & Joyner, M. J. (2013). VO₂max trainability and high intensity interval training in humans: a meta-analysis. PLOS ONE, 8(9), e73182. PLOS ONE →
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