VO2 Max Explained in 5 Minutes

Simple explanations of not-so-simple concepts.

Terence Shin, MSc, MBA



VO2 max is arguably one of the most important health metrics today, and yet, it’s not very clear to most people what it is. And so, my goal is to distill to you what VO2 max is as simply, yet as comprehensively, as possible.

If you have a family history of cardiovascular diseases, are a high-performing athlete, are an individual entering or already in the latter half of your life, or simply care about your health, then you will find a lot of value in learning what VO2 max is all about!

With that said, let’s dive right into it.

Point #1: First, you need to know why our body needs oxygen.

Oxygen plays a pivotal role in the human body, primarily in energy production through a process known as cellular respiration. This process involves a series of biochemical reactions where nutrients such as carbohydrates and fats are converted into adenosine triphosphate (ATP), the primary energy carrier in cells. This conversion is not just a simple one-step reaction but a complex set of processes involving multiple biochemical pathways.

Aerobic metabolism refers to the set of these processes in cellular respiration that specifically require oxygen. This is where oxygen’s critical role comes into play. Aerobic metabolism includes the Krebs cycle, also known as the citric acid cycle, and oxidative phosphorylation.

Aerobic metabolism is responsible for most of the ATP produced during cellular respiration. Compared to anaerobic processes (those that do not require oxygen), aerobic metabolism can generate up to 15 times more ATP from each glucose molecule. This high yield underlines why oxygen availability is so crucial for energy production.

Therefore, the more oxygen available to your cells, the more efficiently they can perform aerobic metabolism, and the more energy they produce.

Point #2: So what exactly is VO2 Max?

I previously concluded that more oxygen equals more energy.

However, the relationship between oxygen consumption and energy production isn’t…