Also referred to as maximal oxygen uptake, VO2MAX is widely considered the most accurate measurement of cardiovascular fitness. Measuring your VO2MAX can give you an inside look into your current fitness levels. VO2MAX is a measurement of the maximum (MAX) volume (V) of oxygen (O2) your body can take in and use during intense aerobic exercise. It’s measured in milliliters of oxygen consumed in a minute per kilogram of body weight (ml/kg/min). You can get your level checked at a fitness facility that offers VO2MAX testing—or more recently, your smart watch or fitness tracker may have that feature. Active men between the ages of 18 and 45 typically score between 45.5 to 46.4 ml/kg/min, whereas very active men often reach 85 ml/kg/min or above. Active women within the same age group usually fall between 33.0 and 36.9 ml/kg/min, with very active women reaching 77 ml/kg/min or more.

According to the World Health Organization, cardiovascular diseases (CVDs) are the leading cause of death worldwide, and almost 1 in every 3 deaths in the United States in 2013 was caused by a CVD. Studies have shown that physical activity and cardiorespiratory fitness (CRF) are inversely associated with CVD and mortality, and even a small increase in CRF is related to a significantly lower risk of death. CRF is a measure of the maximum oxygen uptake per minute per kilogram body weight. Typically VO2MAX decreases with age; thus, a younger individual would be more likely to have a higher VO2MAX than an older individual. 

Participants from the Copenhagen Male Study, established in 1970, were included and stratified into four age-adjusted maximal oxygen consumption (VO2MAX) categories: below the lower limit of normal (lowest 5%); low normal (45%); high normal (45%); and above the upper limit of normal (top 5%). The lowest group had a VO2MAX of about 20.7, while the highest group had about 49.6. The average was 32.9. A total of 5,107 men with a mean age of 48.8 years were included in the study. During the 46 years of follow-up, 4,700 (92%) men died; 2,149 (42.1%) of the men died of cardiovascular disease. Compared with the lowest level of cardiorespiratory fitness, low-normal CRF was associated with 2.1 years, high-normal with 2.9 years, and the upper limit of normal with 4.9 years longer life expectancy on average. Each 1 ml/kg/min increase in VO2MAX was associated with a 45-day increase in longevity. The benefits of higher midlife CRF extend well into the later part of life. Higher CRF was associated with lower prevalence of hypertension, lower body mass index, and higher physical activity.

Higher levels of VO2MAX were associated with increased longevity—up to 5 years longer. The study suggests that VO2MAX is an even stronger predictor of long-term mortality than conventional risk factors, such as hyperlipidemia (high cholesterol), obesity, hypertension (high blood pressure), and insulin resistance. 

After learning this, I am ready to invest in a smart watch that measures VO2MAX to see where I stand. If I am below 50 ml/kg/min—where the study saw a five-year boost to longevity—I will try my best to improve. I have read that the best way to increase your VO2MAX is to do a mix of lower-intensity and high-intensity aerobic workouts. So, should you be watching your VO2MAX? If you want to maximize your lifespan, the answer appears to be “yes”.