Why VO2max matters and how to boost yours

What if I told you the health metric most consistently associated with longevity is essentially never even tested at annual physicals or doctor's visits? That's right: you've likely heard us comment before on VO2max as an incredibly important number to know for predicting both your lifespan and healthspan.

This number has long been neglected by modern medicine as it has historically been thought of solely as a marker of exercise performance. Additionally, as we'll see in a moment, there is no one bodily system that this metric necessarily belongs to. Therefore, it has never exactly been adopted by any one medical specialty. Lastly, we've made no secret that our country's healthcare system has completely failed to prioritize preventive medicine as a whole, of which measuring and tracking VO2max would be the ultimate form.

So, what does VO2max mean, and what does it tell us? VO2max is a rate that essentially tells us the maximal amount of oxygen our body can take from our environment and utilize for metabolism over time. To understand everything this informs us about, we need to consider the pathway of oxygen throughout the body.

First, we breathe in oxygen from the atmosphere, traveling through our lungs until it reaches the alveolar air sacs. There are two things to mention at this stage. The first is that you could technically consider that at higher altitudes, there is a lower partial pressure of oxygen just available in the atmosphere to consume, and that’s why VO2max (and overall intense cardiorespiratory performance) tends to decline at high altitude. The solution to improving VO2max, though, is not simply to move to sea level. If anything, it’s the opposite, because what’s truly predictive of health is not your VO2max due to the environment, but due to your body’s adaptations of how it takes in and utilizes oxygen. We know that individuals who chronically live at high altitude have beneficial cardiorespiratory adaptations to that low partial pressure of oxygen (in fact, you can often see significant adaptations after just a couple days at altitude). All of that said, the second and far more important takeaway from this stage of air travel through our lungs is that any form of respiratory disease will clearly impact this metric, of which there are several that can be chronically burdensome to health: chronic obstructive pulmonary disease (COPD), asthma, cancer, etc.

Next, once the air we breathe in reaches the alveoli, it must diffuse across the membrane into the bloodstream. Again, several pulmonary pathologies can impact this diffusion process and thus weigh down VO2max, such as pneumonia, pulmonary fibrosis, etc. Once oxygen has diffused into the bloodstream, it is then the job of the cardiovascular system to appropriately circulate the blood to all tissues of the body. You guessed it: any circulatory dysfunction, and that will impact VO2max as well. At this point, we probably don't need to emphasize the importance of good cardiovascular health for both length and quality of life, as disease of this category is the number one chronic killer in the country.

The oxygen then arrives at the tissue, and the next question is, how much tissue is available there to metabolize it? This is, of course, a function of our musculoskeletal system and how much lean tissue we have in order to metabolize oxygen for high-intensity efforts, such as one that would push us to our VO2max. This is one of many reasons that we would advocate for individuals focusing on strength training and other efforts to improve strength and muscle mass for reasons other than merely mechanical functionality, performance, or appearance. This tissue is highly metabolically active and beneficial to have not merely for VO2max and the oxygen side of the equation, but also fuel consumption and overall metabolic health.

Then, you could even say there is a question of how many mitochondria are available to metabolize this oxygen, as well as how optimally those mitochondria are functioning. This is where all of our discussion of low-moderate intensity zone 2 training comes into play, as this can not only increase the density of mitochondria among muscle fibers (via stimulation of mitochondrial biogenesis), but also improve the function of individual mitochondria within each cell and their aerobic metabolism.

That may have been an excessive description of the journey of oxygen from the atmosphere to the cellular level, but it even cut out components. For example, one needs the neurological function to send a sufficient stimulus to their muscular tissue to work at a significant level of intensity to maximize VO2max, which can also be limiting to the metric for an untrained individual rarely utilizing those neuromuscular pathways. The take-home point from all of this is that if any one component of this pathway is disrupted with pathology of any kind, that will result in an impairment of VO2max. Thus, if we regularly tracked one's VO2max, it should in theory be one of the first things to fall in the event of an issue arising anywhere along the way, and tee us off to considering problems at bay in this process. On the contrary, if one maintains a high-level VO2max, we can be relatively assured that they are likely in good health, at least with regard to the general functionality of these critical bodily systems: cardiovascular, pulmonary, neurological, metabolic… Put it this way: if you have even relatively early onset of disease in any of these realms, it’s hard to imagine you would still be able to preserve an elite VO2max.

VO2max can be boosted in several ways, and the largest magnitude of benefits truthfully comes by going from no exercise to any exercise. However, to optimize all of these systems, particularly as we age, we still want this number to be as high as possible, which is why we should generally try to train intentionally with a diversified program incorporating both cardiorespiratory and strength training. For VO2max in particular, we are going to get the most benefit from high-intensity efforts, such as interval training. The exact timing protocol is still highly debated in the literature, ranging from some doing just 20 seconds all-out of any exercise, 10 seconds off for 8 rounds (4 minutes total, the “Tabata protocol”), to others doing 4 minutes at max intensity, 4 minutes off for 5 rounds (40 minutes), to others doing a 1 minute on, 1 minute off. Regardless of what you choose, it's generally considered beneficial to incorporate high intensity interval training (HIIT) to your regimen at least 1-2 times per week. We strongly encourage multiple hours per week of zone 2 training for several other reasons, but while this can still benefit your VO2max, it does so to a lesser extent than directly intentional interval training. To conclude, the most important extrapolation from all of this is that if we can incorporate any degree of regular movement and activity, preferably with some component of high intensity, our health will be significantly better off for it.

Subscribe to our monthly newsletter

Support our community projects

DISCLAIMER:

All content and information provided on or through this website is for general informational purposes only and does not constitute a professional service of any kind. This includes, but is not limited to, the practice of medicine, nursing, or other professional healthcare services. The use of any information contained on or accessed through this website is at the user’s own risk. The material on this site or accessible through this site is not intended to be a substitute for any form of professional advice. Always seek the advice of a qualified professional before making any health-related decisions or taking any health-related actions. Users should not disregard or delay in obtaining medical advice for any medical condition they have, and should seek the assistance of their healthcare professionals for any such conditions.