VO2 Max Is a Key Factor in Hitting Your Fitness Goals—Here's What You Need to Know

Anyone who has begun the process of getting in shape knows that there are many different factors involved. For example, both cardio exercise and weight training should be involved, and it's a good idea to try different types of exercise so that you know what you enjoy best and what works well for your body. But on the quest for better fitness, there are some more technical elements that are helpful to know about, too. Having more knowledge under your belt makes you more easily able to achieve the goals you're aiming for.

One of those more technical aspects of improving your fitness is learning about VO2 max. While it sounds like a sports drink or a piece of workout equipment, it's actually a pretty straightforward biological mechanism. Ahead, with the help of certified personal trainers Katie Kollath and Steve Stonehouse, we'll teach you everything you need to know about VO2 max, including what it is, why it's important, and how you can improve yours.

What Is VO2 Max?

Let us assure you, VO2 max sounds more complicated than it is. It's about oxygen—hence the "O2" in the name—and we all know that oxygen is an important part of exercising. After all, the harder you work out, the heavier you're bound to breathe.

"VO2 max is the maximum amount of oxygen your body can utilize during exercise," says Kollath, who tells us that the term is also known as "max oxygen consumption." Stonehouse adds that "this measurement is considered the best indicator of cardiovascular fitness and/or aerobic capacity (endurance)."

VO2 max generally applies to the amount of oxygen your body can use during intense exercise. It's not usually used in relation to gentle workouts, because a gentle workout isn't going to max out your breathing capacity. It's also specific to your cardiorespiratory fitness, meaning cardio activity. Kollath tells us that "the more oxygen a person can utilize, the more energy they can produce during cardiovascular exercise."

Producing energy is of course important, which can probably lead you to assume that having a good VO2 max is a pretty big deal. That is indeed the case. Let's learn more about why VO2 max matters.

Why Is VO2 Max Important?

VO2 max matters because it determines how well you can use and produce energy. Stonehouse breaks it down for us, saying that "as you breathe in oxygen, your lungs absorb it and turn it into energy called adenosine triphosphate (ATP)." This is a big deal because "ATP powers your cells and helps release the carbon dioxide (CO₂) that’s created during your respiratory process when you exhale." That means that "'the greater your VO2 max, the more oxygen your body can consume, and the more effectively your body can use that oxygen to generate the maximum amount of ATP energy."

"Improving aerobic fitness and increasing VO2 max can reduce the risk of cardiovascular disease and help maintain overall fitness throughout life," says Kollath, who adds that VO2 max is "a helpful measurement for endurance athletes, as they will want to measure and improve this number over time to increase performance." This means that as you become more fit, VO2 max gives you another way to measure exactly how fit you're becoming. We already have some tools that tell us, like how much weight we can lift or how well our clothes fit, but this is a much more technical way to really gain a deeper understanding of our cardio fitness level.

Lastly, checking your VO2 max is helpful because it doesn't stay the same throughout life. Kollath says that "generally, VO2 max begins to decline with age and aerobic activity can help maintain or improve it."

How Is VO2 Max Measured?

Now that we understand why VO2 matters, let's look at how it's calculated. "VO2 max is measured in liters per minute, (l/min), or milliliters per minute per kilogram of body weight, (ml/min/kg)," says Kollath. While most of us don't generally think about oxygen in terms of liters, that's the way it works for any situation where oxygen is measured. That includes the type of supplemental oxygen given to people with respiratory issues. Stonehouse adds that "VO2 max tests are typically conducted in clinical settings by a doctor or cardiac specialist of some kind."

Kollath explains that while the most accurate version of VO2 max testing is done in a clinical setting, they are other ways for the average person to go about testing theirs. "There are multiple tests that can be used to estimate VO2 max, with submaximal testing being the most popular and most accessible option in the general fitness setting," she says, adding that testing in a clinical environment isn't as common because it "requires specific training protocols and equipment (either a treadmill or a bike, usually, and a face mask that measures air volume and breathing levels)."

For the more accessible version of VO2 max testing, Kollath explains that "participant heart rate, speed or power (watts), and oxygen uptake are all measured in phases and at specific loads and thresholds." She says that from there, "this data can then be used to develop a training program with appropriate training zones for an individual athlete."

How to Improve Your VO2 Max

VO2 max is all about how your body uses and produces energy, so it makes perfect sense that you want it to be as optimized as possible. Fortunately, there are numerous ways that you can go about improving your VO2 max. These are our trainers' top choices.

• Train at a high intensity: "Working in the upper ranges of your max heart rate can increase the volume of blood your heart can pump with each beat," says Stonehouse. This will in turn improve your VO2 max.
• Practice intervals: Stonehouse says that studies have shown "that interval training produces better VO2 max improvements than general, continuous aerobic exercise."
• Combine those two into HIIT workouts: "HIIT involves working at a near-maximal intensity for a short interval followed by a longer rest interval," says Kollath. "With this style of training, you are mainly training anaerobically (without oxygen). Some studies show that HIIT training can significantly increase oxygen delivery during exercises, therefore increasing VO2 max."
• Make sure your training program is comprehensive: That means it includes cardio and strength training. "A properly designed training program can help incorporate various training zones over time and improve VO2 max," says Kollath. "Additionally, because strength directly impacts power output and resistance training can also lead to more efficient movement patterns and a decrease in injury risk, a structured resistance training program can also aid in improving VO2 max over time. Pairing a resistance training program with a cardiovascular program will produce the best results for improving VO2 max."

The Final Takeaway

VO2 max is a term that refers to the maximum amount of oxygen your body can utilize during exercise. It's important because when you breathe in oxygen, your lunges turn it into energy, called ATP. The better your body can utilize oxygen, the more energy it can produce, and the more fit and strong you can become.

If you want to improve your VO2 max, your best bet is HIIT workouts. They should combine both cardio and strength training exercises, and you should perform each for short bursts of time. VO2 max naturally declines with age, so there's no better time than the present to get yours on track.