How to Use VO2 Max Testing
In Understanding VO2 Max we discussed what VO2 max is. Today we are going to show how VO2 max testing can be used to design an exercise program. To review quickly, VO2 max is the amount of oxygen the body can take in and transport throughout the body in one minute. It’s an indication of fitness, and a function of how well the cardiovascular, pulmonary, and musculoskeletal systems are working together.
To understand how VO2 max testing can be used to design an exercise program there are two terms we need to become familiar with – aerobic threshold and anaerobic threshold. At the end of the day you want to know the heart rate that corresponds to the anaerobic threshold and then use that heart rate to design an exercise program.
- Aerobic threshold is the minimum heart rate (or intensity) that must be reached before improvements in aerobic fitness can occur. The more aerobically fit one is the higher the intensity (and therefore heart rate) must be for further improvements to occur. Those who are more fit are said to have higher aerobic training thresholds.
- Anaerobic threshold is the intensity of exercise above which further improvements in aerobic training are not possible. The anaerobic threshold is the point at which a sudden increase in blood lactate occurs. It’s also the point at which carbon dioxide production exceeds the intake of oxygen. This point where carbon dioxide production exceeds oxygen intake can be precisely measured during VO2 max testing.
Exercising above the anaerobic threshold involves performing very intense exercise and very intense exercise cannot be performed for prolong periods. Interesting and beneficial hormonal responses take place once the anaerobic threshold is exceeded.
At lower levels of intensity – those within the aerobic training zone (intensity between aerobic threshold and anaerobic threshold) – there is little change in hormones like catecholamines, glucagon, and growth hormone. However, at higher intensities – intensities above anaerobic threshold – there is an increase in catecholamines, glucagon, growth hormone, and testosterone. The rise in these hormones positively affect body composition and regulate energy usage.
The heart rate at which anaerobic threshold occurs can be used to design an exercise program. Performing high intensity interval training by periodically exercising at intensities above anaerobic threshold provides beneficial physiologic changes not seen at lower intensities. In addition to the hormonal changes another benefit is a higher EPOC or excess post-exercise oxygen consumption which is a fancy way to say higher metabolism after the exercise is over. This facilitates fat loss.
VO2 max testing can also be used to monitor changes or improvement from performing a specific exercise program and adjusting it accordingly to get the maximum results and health benefits.
If VO2 max testing is not available you can use 85% of your predicted maximum heart rate to estimate the heart rate at which you reach anaerobic threshold – but this equation does not hold true for each individual so it’s best to consider VO2 max testing.
See related articles.