What is VO₂ Max
A VO2 Max Test is a measurement that reflects a person’s ability to perform sustained exercise. It is generally considered the best indicator of cardiovascular fitness and aerobic endurance. The actual measurement is “milliliters of oxygen used in one minute per kilogram of body weight.” It is suitable for a wide range of individuals, from the sedentary to elite athletes.
VO2 Max is the maximum rate of oxygen consumption that can be attained during the most intense exercise possible. The measurement requires that the subject breathe into an oxygen consumption analyzer during an all-out effort (usually on a treadmill or bicycle) as part of a graded exercise protocol. These protocols involve specific increases in the speed and intensity of the exercise. While exercising, the person wears a mask to collect all the air he breathes in and out for a measurement of the volume of exhaled gas and the concentration of oxygen in that exhaled gas. This determines how much oxygen is used during each minute of the exercise test.
A person’s oxygen consumption rises in a linear relationship with exercise intensity — up to a point. There are specific physiological markers (AeT, AT) that can be detected throughout the test as oxygen consumption is measured. Eventually, oxygen consumption plateaus even if the exercise intensity increases. When the person is no longer able to keep up with the oxygen demands of his muscles and complete fatigue forces him to stop exercising, then his oxygen consumption has reached a maximum, and VO2 Max can be calculated. The test usually takes between 10 and 15 minutes
A complete VO2 Fitness test can give trainers and clients the tools to set realistic goals and assess improvement. Studies show that previously sedentary people training at 75% of aerobic power for 30 minutes, 3 times a week over 6 months increase VO2 Max an average of 15-20%. Many people are inefficient exercisers, with no understanding of what specific heart rate, intensity or duration would best help them reach their specific goals such as fat burning, endurance training, or cardio conditioning. An initial VO2 Max test can clarify the specific target heart rates that will enable each individual to reach their fitness goals more effectively, with less fatigue and fewer injuries. Periodic retesting provides motivating feedback as the fitness program progresses.
The test also determines the number of calories burned during every level of exercise, providing valuable information when designing a weight loss program. And if CO2 is measured during the test, a Respiratory Exchange Ratio (RER) can determine the proportion of energy coming from carbohydrates and fats at various levels of exercise intensity. Since physical conditioning and exercise intensity affect these proportions, this information can be very helpful when designing a workout intended to burn fat.
VO2 Max testing is a valuable tool for serious athletes to assess performance and evaluate training regimens. Even though extensive training can sometimes cause an athlete to reach a plateau in VO2 Max, he can still use his VO2 Max test results to make further improvements in performance. This is accomplished as he pushes to increase anaerobic threshold (AT) and maintain that threshold for longer periods of time. This enhances both endurance and cardiovascular performance.