How Does VO₂ Max Explain Your Biological Age?

Ageing is inevitable. Everyone ages and the numbers in your passport cannot be diminished or reversed. However, you can have a drastically lower fitness age than your real age; you may be 50 with a fitness age of 25. As such, your real age becomes less of an indicator of your future and more of an indicator of how many years you have lived. The important metric is the fitness age.

VO₂ max is a good indicator of cardiovascular health as well as fitness and age. So, by improving it can we outsmart the flow of time and be forever young? Unfortunately, it is not all roses. But first, let’s begin with what VO₂ is.

VO₂ max is the one physiological parameter that anyone who is involved in endurance activity has heard of. A first-order analogy is equating it to the ‘size of your engine’ since the metric tells you how much, and how quickly, you can take oxygen from the air into your lungs, inject it into your blood and use this energy to fuel various metabolic processes. In other words, it is a rate of how much oxygen per unit of time you can process. This is particularly important for athletes as a higher VO₂ max means they are able to use their muscles more efficiently.

Ageing vastly contributes to the decline in cardiovascular and muscular health which, in its turn, leads to a drop in VO₂ max levels.

The peak of the maximum volume of oxygen comes when a person is around 20 years old. A decline starts around the age of 25-30 when VO₂ max begins to drop by about 10% per decade. As a person reaches older ages, such as 60-70, the decline in VO₂ max becomes even more pronounced. At the age of 70, the VO₂ max may drop by up to 23%. Studies have shown that this decline in maximum oxygen uptake is more significant in males than females.

Regardless of how fit a person may be, the ageing process takes a toll on all individuals, including elite athletes. Even though the decline can be significantly slowed or even reversed back through regular physical activity and exercise, it is ultimately an inevitable aspect of ageing for everyone.

The average ‘good’ level standards are dropping as the age increases. For example, a VO₂ max of 33 mL/kg/min is considered to be ‘poor’ in the age of 18-25 but it is a ‘good’ level for people aged 65+.

From this, we may grasp an idea of your comparative ‘physiological’ age. If your VO₂ max is higher than the age group in which you are, then you are ‘younger’ than your peers at your age. It is also true in reverse.

Age-related decline in VO₂ max results from multiple factors, including changes in the cardiovascular and respiratory systems, as well as changes in muscle mass and function.

One major factor is the decline in the number and function of mitochondria, the organelles in cells that produce energy. As we age, our muscles lose muscle fibres, which leads to a decline in muscle mass and strength. This decrease in muscle mass results in a decline in the ability to produce energy aerobically, which in turn results in a decline in VO₂ max.

As we age, our muscle mass decreases by approximately 3–8% per decade, and by even more after we turn 60.

As we age, our heart’s ability to pump blood decreases, which can reduce the amount of oxygen that is delivered to the muscles during exercise. This can also result in a decline in VO₂ max.

Additionally, the lungs’ capacity to move oxygen into the bloodstream and the efficiency of the body’s ability to transport oxygen to the muscles also decreases with age which can affect VO₂ max.

You may ask what is an acceptable VO₂ max, and what level you need to be healthy. However, the definition of a ‘good’ VO₂ max is not universal for all people.

In the 1990s, Olympic skier Bjørn Dæhlie achieved the highest VO₂ max ever measured, 96 ml/kg/min.

Norwegian cyclist Oskar Svendsen reportedly topped Dæhlie with his VO₂ max of 97.5 ml/kg/min, however, scientists are still investigating the accuracy of the results.

The key factors that define your VO₂ max are:

1. Age – as we age our VO₂ max declines (see below).

2. Gender – men due the physiology and genetics have higher levels of VO₂ max than women. This may define a serious and unavoidable difference in athletic sports between men and women. For a 25-year-old male, a good VO₂ max is 45.4 mL/kg/min, while for a 25-year-old female, it is 39.5 mL/kg/min.

3. Fitness level has a serious influence – people of the same age but different fitness levels and cardiovascular health can have a 2 times difference in VO₂ max. Inactive males and females achieve VO₂ max of around 35 and 40 mL/kg/min, respectively. A male elite runner’s VO₂ max has been recorded at 85 mL/kg/min, and a female elite runner has been recorded at 77 mL/kg/min.

4. Altitude – as the altitude is higher, VO₂ max is lower. This is because of the decrease in pressure that comes with an increase in altitude. This pressure leads to a lower blood oxygen saturation and thus VO₂ max.

For a better understanding of how the classification moves across genders and ages, see the VO₂ max charts below developed by the Copper Institute.

If your VO₂ max is higher than the age group in which you are, then you can consider yourself ‘younger’ in terms of fitness age. It is also true in reverse.

Not enough? Here is more from our colleagues

The Peter Attia Drive is a weekly, extremely profound podcast focusing on maximizing health and longevity. These videos are created by Peter Attia, M.D., who is a certified physician. He specializes in nutrition, exercise and sleep physiology, and emotional and mental health to enhance the quality of life and increase lifespan.

In this short, informative podcast, Peter shares information about the age-associated decline in aerobic capacity and muscle mass.

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