What Is a Good VO2 Max? Decoding Your Fitness Potential

Sometimes, everyday moments like climbing a flight of stairs or carrying groceries unexpectedly leave you breathless or fatigued. This might be more than just a sign of a long day; moments like these can reveal important clues about your VO2 max.

But what exactly is VO2 max, and why should it matter to you? More importantly, what counts as a ‘good’ VO2 max, and how can you boost it regardless of where you are in your fitness journey?

In this article, we will explore the science behind VO2 max and unpack why it’s a crucial indicator of cardiovascular and respiratory health. We will also look at practical ways to use it to elevate your fitness level, whether you are a fitness enthusiast or just starting your fitness journey.

What is VO2 max?

VO2 max is one of the clearest indicators of cardiovascular fitness. It is a measure of the maximum amount of oxygen uptake during exercise. It is reached when oxygen consumption remains steady despite increasing exercise intensity.

It’s widely considered one of the best measures of aerobic fitness, but to truly understand what VO2 max tells us, we need to look at oxygen consumption during exercise and why this matters at the cellular level.

When you exercise, your muscles demand more energy, and oxygen is essential to meeting that demand. As you breathe in, oxygen moves from your lungs into the bloodstream. Your heart then pumps this oxygenated blood to fuel your muscle cells and produce energy. In turn, carbon dioxide is generated as a waste product and carried back to the lungs to be exhaled. The more efficiently your body manages this cycle, the better your endurance and aerobic fitness.

Why does VO2 max matter for you?

VO2 max is relevant for anyone who wants to move through life with more energy, less fatigue, and better long-term health.

Your maximal oxygen consumption reflects your cardiorespiratory fitness — how well your heart, lungs, and muscles work together to deliver and use oxygen. This translates into better endurance, quicker recovery, and even a lower risk of cardiovascular diseases and type 2 diabetes.

In daily life, this means more energy for everyday tasks, less breathlessness from stairs or walking, and better cardiovascular health and physical resilience overall. Whether you're active or just getting started, improving your VO2 max can enhance both your fitness and your quality of life.

How is VO2 max measured?

VO2 max is the maximum amount of oxygen your body can use (mL) per kilogram (kg) of body weight per minute, expressed as mL/kg/min. There are several ways to measure it with some being more accurate than others.

Maximal lab testing — the gold standard

The most accurate way to measure VO2 max is through a maximal graded exercise test under professional supervision in a clinical or sports lab. This involves exercising on a treadmill or stationary bike while wearing a face mask that measures exactly how much oxygen you consume at peak effort. Because this testing requires pushing to exhaustion, it’s generally reserved for athletic testing, clinical assessments, or research.

Submaximal exercise testing — safer and more accessible

For most people, VO2 max can be estimated using submaximal exercise tests that don’t require going to full exertion. These tests predict VO2 max based on your heart rate response to a lower-intensity workout.

Some common examples of submaximal exercise testing include:

While not as precise as lab tests, these can still give a reasonable estimate, especially when conducted properly.

Fitness trackers — convenient but variable

Most fitness watches, such as those from Garmin, Apple, Fitbit, or Polar, estimate VO2 max using data from your heart rate, activity patterns, and pace. However, these watches are only based on algorithms, so although they’re convenient, their accuracy can vary depending on factors like sensor quality, your fitness level, and how consistently you wear the device.

What's considered a good VO2 max?

When you get your VO2 max score, you might wonder, “Is this good?” The short answer is — it depends. Unlike established blood pressure ranges, there's no single ‘ideal’ VO2 max number for everyone. Instead, what’s considered ‘good’ varies by age, sex, and your personal fitness goals.

As we age, our fitness typically declines, even in active individuals.​​ A VO2 max of 45 can mean very different things depending on your age group; what’s considered excellent at 50 years old might only be average at 25.

Biological sex also plays a role. Research shows that people assigned female at birth (AFAB) typically have less lean muscle mass and tend to naturally have more fatty tissue, which affects overall body composition and can result in lower relative VO2 max scores compared to people assigned male at birth (AMAB). This is why charts are sex-specific for fair comparison.

Let’s take a closer look at the typical VO2 max ranges for AMAB and AFAB individuals:

Can you improve your VO2 max?

You can improve your VO2 max, and the gains can be surprisingly significant, especially if you're just starting out.

To increase your VO2 max, the key is to challenge your heart, lungs, and muscles to force them to become more efficient. The best forms of exercise include:

• Cardiovascular endurance activities like running, swimming, cycling, rowing, and cross-country skiing
• Interval training, particularly high-intensity interval training (HIIT)
• Steady-state cardio at moderate to high intensity

While pushing hard during workouts helps, consistency is what truly drives long-term improvements. Sticking to a regular training schedule leads to gradual cardiovascular adaptations that boost your VO2 max over time.

VO2 max: your aerobic engine and benefits

TOC: Benefits

When people talk about VO2 max, they often focus on athletic performance, for example, how fast you can run or how hard you can push in a workout. But there’s a much deeper story behind that number. Your VO2 max isn’t just about aerobic capacity; it can strongly indicate your long-term health and cardiovascular resilience.

Research published in the Journal of the American Medical Association (JAMA) found that cardiorespiratory endurance (as measured by VO2 max) was a stronger predictor of early death than smoking, high cholesterol, or diabetes. It also concluded that those with the highest levels of cardiorespiratory fitness had the longest life expectancy, even compared to those with moderate fitness levels.

Furthermore, a 2018 study tracking men over 46 years old found that higher VO2 max in midlife was strongly linked to a lower risk of death. Even decades later, those with greater cardiorespiratory fitness lived longer, highlighting the lasting impact of staying fit even in your 40s and 50s.

Aerobic fitness and long-term wellness

As you age, your VO2 max naturally declines, but regular aerobic activity can slow that decline and preserve independence, mobility, and energy. Maintaining your ‘aerobic engine’ is a key part of aging well and can be more impactful than simply losing weight or lowering blood pressure alone.

Dr. Steven N. Blair, a renowned exercise scientist and professor at the Arnold School of Public Health at the University of South Carolina, emphasized the significance of physical fitness in reducing mortality risk. In an interview published in the Journal of Sport and Health Science, he stated:

A general summary is that obese individuals who are at least moderately fit, which can be achieved by meeting the PA [physical activity] guidelines, have one-half the risk of dying in the next several years when compared to normal-weight individuals who are unfit. I have been often criticized on this point, but my response is: do some research with good measurements of PA, obesity, and health outcomes, and show that we are wrong!

Dr. Steven N. Blair

According to Dr. Blair, his research challenges conventional assumptions about health by suggesting that physical activity and fitness may be more important than body size in reducing mortality risk.

Final thoughts

Top endurance athletes practically dedicate their lives to improving their VO2 max. For most people, however, a good VO2 max is understood in terms of so-called normal values.

You don’t need elite training or fancy equipment to boost your fitness. Whether you're tracking VO2 max or simply noticing improvements in your energy, heart rate, or walking pace, the real key is consistency. Over time, small efforts add up, and seeing that progress can be a powerful motivator for lasting change.

Just remember: VO2 max is only one part of the picture. Rest, hydration, nutrition, and a balanced, healthy lifestyle are just as vital for recovery and long-term health.

Everyone’s health journey is different. Before starting any new exercise program, especially if you have underlying medical conditions, it's best to consult with a healthcare provider or qualified fitness professional to ensure your approach is safe and effective for your needs.