What Is VO2 Max?

Everyone knows that keeping fit is a good idea. There are plenty of proven health benefits to a healthier, more active lifestyle. But how can you work out just how fit you are?

Well, that’s what VO2 max is for. And what is VO2 max? Read on and find out why it is so important to your health!

Full Steam Ahead

VO2 max, also known as maximal aerobic capacity or peak oxygen uptake, is the measurement used to express your highest possible rate of oxygen consumption while exercising. It is the most reliable method for measuring cardiorespiratory fitness (CRF), and can be used as an indicator of your overall fitness.

The name itself is made up of three parts: “V” is for volume, “O2” is for oxygen, and “max” is for maximum. VO2 max can be measured in two ways: as a relative rate, for example in milliliters of oxygen per kilogram of body mass per minute (mL/(kg·min) – something of a mouthful!); or as an absolute rate, such as in liters of oxygen per minute (L/min).

The relative rate is used in the field of endurance sports, where it is used to measure athletes’ comparative performances. It is only of limited use though, because a 2013 study published in the Journal of Experimental Biology showed that VO2 max doesn’t necessarily change in line with body mass. This means it needs to be subjected to the mercies of statistical analysis rather than being an accurate measure on its own merits.

Gotta Push Those Numbers Up

So, how do you find out what your VO2 max is? The most accurate method used during athletic and clinical tests involves hooking you up to sensors while you are on a treadmill or exercise bike. The intensity of the exercise is increased over time, and they measure your breathing rate and how much oxygen and carbon dioxide you are breathing in and out.

Eventually, you will reach your VO2 max when the amount of oxygen you consume stops going up despite the increasing physical workload. Essentially, they push you to your limit, then give you a number to tell you what it is.

Finding out your exact VO2 max isn’t always possible, or even a good idea for those with certain health conditions, as it involves such intense exercise. Fortunately, there is a range of ways to estimate it, including using the ratio between your resting and maximum heart rates, and the multi-stage fitness test (a.k.a. the dreaded beep test). Some modern fitness devices compare how much exercise you’ve done to factors like your age, height, weight and gender to find an estimate.

Give Me Your Digits

Now that you know what VO2 max is, and some of the ways that it can be determined, you’re likely wondering where you stand on the scale. Well, the average guy who hasn’t done any training will be sitting at around 35–40mL/(kg·min), while an average girl will be around 27–31mL/(kg·min). These numbers can be improved by training, though they will sadly but inevitably fall with age.

These fitness levels pale in comparison to elite athletes, mind you. The fittest runners are clocking in at 85mL/(kg·min) for the men, and around 77mL/(kg·min) for the women. The highest relative VO2 max is thought to have been recorded by Norwegian cyclist Oskar Svendsen when he was 18 years old. He managed an incredible 97.5mL/(kg·min).

Fit as a Fiddle

What makes knowing your VO2 max so useful? According to a statement published by the American Heart Association in 2016, it is the most accurate way of assessing cardiorespiratory fitness. This is important to measure, because your fitness level has been shown to have clear links to your risks of contracting a range of diseases, and even to how long you might live.

In 2002, a six-year study among over 6000 US veterans came to that conclusion. Their relative VO2 max levels were compared to their age and other risk factors, and then their death rates were recorded. The least fit subjects, apparently healthy participants and those with cardiovascular disease alike, were four times more likely to die than the fittest subjects.

According to the study, your level of CRF is a more accurate predictor of your risk of death than other known factors like obesity, having diabetes or high cholesterol, or being a smoker.

Live Longer, and Prosper

Now some good news: even the smallest improvement in your fitness can significantly improve your chances of a longer life. The American Heart Association’s statement indicated that just a minor improvement in fitness that should be achievable by the average person can increase your odds for survival by 10 to 25 percent.

Even better for the less sporty among us, the biggest benefits to be gained by upping your fitness are seen at the lower end of the scale. So, the less fit you are, the less you have to do to be improving your life. It’s good to know that you don’t have to be athletic to see returns from more exercise.

That’s no excuse to be lazy though. There are clear links between lower levels of fitness and increased chances of heart disease and overall likelihood of death. The fittest folks, meanwhile, were proven to live longer, and healthier lives, at lower risks of diseases and certain cancers. Maybe it’s time to unretire those old running shoes.

Hitting the Wall, and How It Can Help You

So, what is VO2 max? Simply put, it’s a way of measuring exactly how much oxygen you can pump through your system while exercising. It’s used to measure exactly how fit you are.

Your level of CRF is a reflection of how good your body is at getting oxygen out of the air and into your muscles. It is a very important indicator of your overall bodily health, and can be used to predict your chances of death.

High levels of fitness are linked to longer life and reduced chances of heart disease and cancer. In the least fit people, just a small improvement can massively help their chances for survival. If you want to live a longer, healthier life, you might want to consider how you can raise your fitness level, because every small bit helps.

 

References:

https://www.nejm.org/doi/full/10.1056/NEJMoa011858
https://www.ahajournals.org/doi/full/10.1161/CIR.0000000000000461