What is VO2 Max?

What is VO2 Max? VO2 max is the maximum volume (V) of oxygen (O2) in milliliters that you can use in one minute, per kilogram of body weight, while breathing air at sea level. Oxygen consumption happens to be linearly related to energy expenditure; therefore, when we measure oxygen consumption, we are indirectly measuring an individual's maximal capacity to do work aerobically. Keep in mind that this is one of many components of "fitness" and happens to be a particularly important characteristic for great endurance performances in running, cycling, rowing, cross-country skiing, or even high-altitude alpine climbing. Those individuals who are in better cardiovascular condition will have higher VO2 max values and can exercise more intensely than those who are not as fit. Don't despair if your VO2 Max is fairly low when you first start a training program, studies show that you can significantly increase your VO2 max by regular training and by gradually increasing your activity level until you can work at an intensity that raises your heart rate to between 65 and 85% of its maximum for at least 20 minutes 3-5 times a week.

Why know your VO2 Max? Some people may argue that knowing your VO2 Max is not important, particularly if you are more of a recreational exerciser. Others find that testing and improving on their personal fitness numbers gets them motivated to work harder. Still others will use that piece of information to assess how they compare to others ("standards") who are doing their same sport. By knowing what your current VO2 Max is, you can objectively assess your progress as you improve your cardiovascular fitness. If you, as a 28-year-old male, begin the spring season with a VO2 Max of 35 (considered low) and hope to successfully climb up Rainier in 6 months' time, and you see that other male climbers in your age group who reach the summit average VO2 max of 52, then you have a specific, measurable goal to try to reach as you go through your climbing training program, and you will know exactly when you reach it. This can be particularly important if you happen to live in parts of the country where you don't have access to mountains, but still want to gauge how you're doing with your training compared to others who do.

How to Improve Your VO2 Max
Endurance runners improve their VO2 Max by doing repeats on tracks; climbers can do similar interval training on stairs, hills, or an incline ramp on the treadmill to simulate the climbing they'll be doing in the mountains. One note to add: if your heart rate has not recovered to 120 beats per minute in the rest interval (or the descent of the hill/stairs), extend the recovery time before repeating the interval. Eventually, as your cardiovascular system improves, you'll be able to stick to the recovery times between the reps.