Each person has a maximum capacity to deliver oxygen to their muscles during exercise. This value called V02 max can be measured using a graded exercise test. This is usually done on a treadmill so the intensity of the exercise can be slowly increased while oxygen consumption is measured. V02 max is the point where oxygen consumption no longer rises even when the exercise load is increased.
What is the Importance of V02 Max?
V02 max is a measure of how well the heart delivers blood and oxygen to muscles during exercise. It’s also a measure of a person’s aerobic capacity. Not surprisingly, V02 max or aerobic capacity varies per individual. As you might expect, it would be low in someone who had poor heart function due to heart disease and high in a competitive long distance runner.
Having a high V02 max could work in your favor if you’re a runner or athlete, and aerobic capacity and V02 max can be increased by varying degrees through cardiovascular training. Some people are able to improve their V02 max through training more than others. What factors affect V02 max or a person’s aerobic capacity?
Not surprisingly, genetics partially determines a person’s V02 max. Research shows that heredity may account for as much as 60% of an individual’s V02 max value. Training can increase it to varying degrees, but it’s unlikely that training can turn a person with a low V02 max into a competitive endurance athlete. How much you’re able to increase your V02 max through exercise is also limited by genetics.
Many competitive endurance athletes are born with a higher V02 max, and they are able to increase it even more through training. Cross-country skiers and distance runners usually have the highest average aerobic capacity of all athletes.
Men have a higher average V02 max than women. Even when you take into account body size, men have a V02 max that’s anywhere from 15 to 30% greater than women. This is because women have more body fat than men, smaller hearts and less hemoglobin in their blood for delivering oxygen delivery to muscles.
V02 max declines with age. Once you reach the age of 25, V02 max decreases by about 1% per year. Aerobic training helps to offset some of this decline in aerobic capacity that comes with age. That’s why you occasionally see octogenarian marathon runners.
As already mentioned, men have a higher V02 max than women, and part of this difference is related to their larger body size and greater musculature. When you adjust for body size and composition, some of the difference in aerobic capacity between males and females diminishes. Still, there is a certain gender advantage when it comes to V02 max even if you take body composition and size into account.
Not surprisingly, an aerobically trained, fit person will likely have a higher V02 max than a sedentary person of the same age and sex. It’s possible to increase V02 max through aerobic training by as much as 25%, although each individual varies as to how much they can boost their aerobic capacity. How much they can improve depends on their age, genetics and the intensity of their training.
The Bottom Line?
A higher V02 max means you can deliver more oxygen to the muscles, which means you can run or cycle longer or faster. You can boost V02 max through training, but there are still limitations based on genetics, sex, age, and body composition. Keep in mind, a person’s aerobic capacity isn’t the only factor that determines how successful a person is as an athlete. Exercise efficiency, economy, and motivation are also important factors.
Exercise Physiology. Fifth edition. McArdle, Katch, and Katch. 2001.
Exercise Physiology for Health, Fitness, and Performance. Second edition. 2003.