With the increase in popularity of the CrossFit training model, people have begun to appreciate the benefit of short duration, high intensity workout programs over previously idealized long sustained efforts such as running 5 miles. Largely, this idea focuses around your ability to improve a performance marker of athletic endurance called VO2 max.
VO2 max stands for the Maximum Volume of Oxygen you’re able to intake or consume during exercise. It is measured in milliliters of oxygen used in one minute per kilogram of body weight (ml/min/kg). Oxygen is delivered to your muscle tissues for use in the creation of energy during aerobic exercise. Your VO2 max value is a way to measure physical fitness and is often used as a way to gauge endurance. There are many different ways to measure VO2 max ranging from lab-style conditions to large group situations. A commonly used “rule of thumb” way to measure your VO2 max is by the Cooper Endurance Test designed in 1968 by Dr Kenneth Cooper for the US military (1). Participants are challenged to run for 12 minutes at a steady pace, the distance covered (adjusting for age and gender) is a measure of VO2 max.
Beyond baseline introduction to exercise, where a person can drastically improve their aerobic capacity just by starting to partake in aerobic efforts, moderate to highly trained individuals can make larger gains in VO2 max by participating in high intensity bouts of exercise. This benefits the athlete by preventing the physical body from becoming overly stressed with longer workouts and therefore heavily decreasing the chance for injury and saving valuable time.
CrossFit athletes can benefit from knowing and training to improve VO2 max due to their sport requiring the need to be ready for unknown units of endurance work. For examples, improvements in VO2 max will help the athlete when required to perform such workouts as “The Triple Three” (3,000m row, 300 Double Unders, 3 mile run) or the “Murph” (1 mile run, 100 Pullups, 200 Pushups, 300 Squats, 1 mile run). In these types of CrossFit challenges, greater endurance can mean the difference between winning and losing.
VO2 max is also a crucial commodity in the sport of hockey. Duncan Keith, three-time Stanley Cup champion with the Chicago Blackhawks and two-time Olympic Gold Medal winner with team Canada, scored a 71 on the VO2 test while playing college hockey (2). The average for a male on the test is between 30-40. Ten players at this year’s NHL Rookie Combine testing scored a VO2 max higher than 65 (3).
More than just training programs influence VO2 max: body mass and genetics also play a role. Larger athletes will naturally have a higher absolute value and therefore it may be better to look at the outcome as relative to your given size. If you were tested after losing significant body weight there would be a noticeable change in your maximal oxygen consumption, indicating a larger VO2 max.
Analyzing your genetics could allow you a deeper insight into what sized aerobic engine your body inherently or potentially operates at. From this knowledge it is then possible for you to alter training programs to either increase focus on this naturally weaker system or decrease centering upon an already strong capacity level. Unlocking your genetic code can help you garner a more focused insight into metabolic conditioning dynamics that will help lead to future improvement and the harnessing of an unlocked potential.
(1) KH Cooper, 1968. A means of assessing maximal oxygen intake: correlation between field and treadmill testing. The Journal of the American Medical Association, 203(3): 201-204.