VO₂max: Why your endurance outlives your cholesterol level

Hardly any measurement says as much about your life expectancy as maximal oxygen uptake. What's behind it, how to measure it – and how to improve it deliberately.

What VO₂max actually measures

VO₂max is the greatest amount of oxygen your body can take in, transport and use in the muscles per minute – expressed in millilitres per kilogram of body weight per minute (ml/kg/min). Put simply: it shows how powerfully your engine runs at full load.

Behind it lies an interplay of heart, lungs, blood vessels and muscle cells. The better your heart pumps blood with each beat, and the more densely your muscles are packed with mitochondria (the cell's power plants) and fine blood vessels, the higher the value. That is exactly why VO₂max is not just an athletic figure but a mirror of your entire cardiovascular health.

The strongest marker hardly anyone knows

A large study of more than 120,000 people found a clear link: the higher the endurance capacity, the lower the risk of death – with no apparent upper limit. Even very fit people kept benefiting the fitter they were (Mandsager et al., 2018).

The American Heart Association therefore recommends treating cardiorespiratory fitness like a clinical vital sign – about as important as blood pressure or blood sugar (Ross et al., 2016). The crucial difference from many other markers: you can actively and substantially improve VO₂max at almost any age.

How VO₂max is measured

The most accurate value comes from spiroergometry: you exert yourself on a treadmill or bike ergometer while a breathing mask analyses your respiratory gases. Depending on the provider, such a test costs from CHF 150; some services are partly covered by supplementary Krankenkasse cover – worth clarifying in advance.

Somewhat less precise but practical for everyday use are estimates from modern sports watches or simple field tests (such as a submaximal running test). They don't replace a lab, but they are well suited to tracking your trend over the months.

How to improve your VO₂max

The foundation is steady aerobic training in the so-called Zone 2 range: a pace at which you can still speak in full sentences. Two to four sessions per week of 30 to 60 minutes each build your aerobic base.

Short, high-intensity intervals provide the strongest stimulus for VO₂max. A well-studied format is four times four minutes at around 90 percent of your maximum heart rate, with three minutes of easy jogging in between (Helgerud et al., 2007). Once or twice a week is enough – more is not better here, because your body needs recovery to make progress.

Who benefits most from looking at this value

From around the age of 40, VO₂max declines noticeably without targeted training – on average by about 10 percent per decade. Those who counteract early keep a large part of their capacity longer. The value is also ideal for returners, because it makes progress visible and keeps you motivated.

This content is general, research-based information and does not replace medical advice. If you have pre-existing conditions or haven't trained in a long time, get a medical check-up before doing intense sessions.

Sources

• Mandsager K et al. Association of Cardiorespiratory Fitness With Long-term Mortality. JAMA Network Open, 2018.
• Ross R et al. Importance of Assessing Cardiorespiratory Fitness in Clinical Practice. Circulation (AHA Scientific Statement), 2016.
• Helgerud J et al. Aerobic High-Intensity Intervals Improve VO₂max More Than Moderate Training. Med Sci Sports Exerc, 2007.