Maximal Oxygen Uptake (VO₂max) - The Best Measure of Aerobic Fitness

Physiological determinants of VO₂max

There are several factors that affect your aerobic capacity. Most notably your genetics, gender, age, body composition, and training history. Even certain lifestyle choices such as diet and smoking can have big impact on VO₂max.

How to measure VO₂max

Maximal oxygen uptake tests are designed achieve full exhaustion to accurately measure oxygen consumption. In a clinical setting, this is done by putting on a mouthpiece that measures ventilation and oxygen/carbon dioxide concentration of the inhaled and exhaled air during increasingly strenuous exercise. The most common tests involve a treadmill or a cycle ergometer (stationary bike). This test also provides an accurate measurement of your maximal heart rate. Along with resting heart rate, this gives an accurate representation of your heart rate range.

Maximum oxygen uptake is reached when oxygen consumption remains constant despite the increase in workload. VO₂max can then be calculated using the Fick principle: VO₂ = (CO × C_a) – (CO × C_v).

However, you do not need to exert maximum effort in order to calculate maximum oxygen uptake. There are several submaximal tests being used today. These include:

• Astrand treadmill test
• Cooper test
• Heart rate method
• Multi-stage fitness test
• Rockport walking test
• Wingate Test

Submaximal tests utilize their own equations to estimate VO₂max. They are also safer options for people with compromised cardiovascular or respiratory systems. 

How to improve VO₂max

Maximal oxygen uptake can be improved in two ways: with continuous aerobic training or high-intensity interval training. Multiple studies have shown that interval exercise increases VO₂max significantly more than prolonged exercises performed at a moderate heart rate. This is because high-intensity exercises increase oxygen demand and elevate your heart rate much more than less intense workouts.

Continuous aerobic exercises may be a better fit for older adults and beginners who are just starting out their fitness journey. Running, swimming, cycling, rowing, and cross-country skiing are all good examples of effective endurance exercises that can be done at a moderate heart rate. 

High-intensity interval training can be roughly divided into two categories: aerobic and sprint training. Previous studies indicate that aerobic interval exercises improve VO₂max mainly through improved cardiac function. Sprint interval training improves maximal oxygen uptake by increasing the oxidative capacity of peripheral muscles. Some of the best methods to increase VO₂max include:

• Tabata training
• Fartlek training
• Circuit training
• Tempo runs

Whether you enjoy longer workouts or more time-efficient intervals, the most important aspect of training is consistency. Only then will you be able to improve both your health and your performance. 

Final thoughts

Good aerobic fitness is associated with a wide range of health benefits. Better quality of life, longer lifespan, reduced risk of heart disease, stroke, diabetes, and cancer are all strongly related to higher maximal oxygen uptake. It even has beneficial effects on your mental health.

To maintain or improve your maximal oxygen uptake, you should perform cardiovascular endurance exercises three times a week. This can be anything from a short jog in your neighborhood to commuting to work by bike.

VO₂max is also often used to measure the potential for better endurance performance. However, individual differences in lactate threshold, biomechanics, technique, motivation and training have shown that VO₂max is only one part of the equation of better performance.

Did you learn anything new about maximal oxygen uptake? Let us know in the comments.