The VO2 Max Guide: Everything You Need to Know About Enhancing Fitness and Extending Life
Each unit increase is associated with a 45-day increase in life expectancy
What if there was a simple, yet profoundly effective gauge for your overall health, longevity, and vitality? A sort of litmus test for your total healthspan - or ability to lead a healthy and active life decades down the road?
In this deep dive, we'll explore what VO2 max really is and why it's considered the ultimate measure of your aerobic fitness and ability to lead a vibrant, active life.
Cardiorespiratory fitness and VO2 max: the basics
Cardiorespiratory fitness or aerobic fitness means how effective your body can deliver oxygen to your muscles, and how efficiently your muscles can extract that oxygen, enabling you to run (or walk) or cycle or swim. A measurement called VO2 max, is the gold standard for determining your peak cardiorespiratory fitness. While endurance athletes have long used VO2 max to gauge their conditioning and athletic performance, it has significant implications for everyone. Your current VO2 max level serves as an indicator of how active, independent, and mobile you are likely to be in the later decades of your life. It might seem like a morbid topic, but it reminds me of a lyric from my favorite artist, Atmosphere: “the only guarantee in life is a life worth dying for.” By improving your VO2 max through regular aerobic exercise, you can enhance your fitness, ensuring a healthier and more fulfilling life. So, might as well make your life the one you want!
So how does VO2 max work exactly? Let’s say you are sitting on the couch watching a movie. You would probably need about 250 ml of oxygen per minute to produce enough “energy” or ATP in your cells to fuel your body. If you go outside and run uphill, your energy demands will ramp up and your body will require an eight to tenfold increase in oxygen per minute compared to when you were sitting. In order to achieve this increased ATP demand, your body will need to increase the intake and absorption of oxygen. The fitter you are, the better your body is at consuming and converting oxygen to make ATP, and the more you can do.
Cardiorespiratory fitness is probably one of the most important biomarkers and indicators of longevity and healthspan. So much so that having a low VO2 max is like a canary wailing in coal mine. In a study published in the Journal of the American College of Cardiology, looking at data from 750,000 US veterans ages 35-95, researches found that someone in the least fit, 20th percentile has a 4x greater risk of dying than a person in the top 2nd percentile in the same age and sex category. Source. Being in the lowest 25th percentile for VO2 max is linked to an increased risk of premature death, a danger on par with diabetes, heart disease, or smoking.
Data reprinted with permission from The Cooper Institute®. For more information, go to www.CooperInstitute.org.
The most potent drug you didn’t know about: exercise
To understand the magnitude of this effect, let’s zoom out more broadly and look at exercise as a whole. Most people know that exercise is good for you in a myriad of ways. But most people don’t realize the absolute potency it has on increasing your lifespan and your healthspan. According to Dr. Peter Attia, a physician focusing on the applied science of longevity, “[VO2 max] has the greatest power to determine how you will live out the rest of your life. It delays the onset of chronic disease pretty much across the board”. There is no intervention or drug that can rival its magnitude of benefit.
The benefits you get from improving your cardiorespiratory fitness have a huge impact on life expectancy. So much so that about each unit increase in your VO2 max is associated with a 45-day increase in life expectancy. The only other drug that has that kind of dose-dependent response at increasing your lifespan would be discovering the fountain of youth.
John Joannidis decided to test this theory by running a side by side comparison of exercise studies versus drug studies. He found that exercise-based interventions performed as well as or better than multiple classes of pharmaceutical drugs at reducing mortality from coronary disease, prediabetes or diabetes, and stroke. Source.
Ways to measure your VO2 max:
The most accurate way to measure your VO2 max is to go to a lab and be tested, which involves running on a treadmill for 12 minutes with a breathing apparatus measuring your oxygen and carbon dioxide levels. It is not the most pleasant experience, but it will give you the most accurate reading. You can usually get it done for around $100.
Treadmill Test: The HUNT3 Fitness Study created a model that lets you calculate your maximum oxygen consumption by pushing yourself to exhaustion on a treadmill at home or at the gym.
Start at a moderate speed and inclination and increase the intensity every second minute until you reach exhaustion. Then calculate your fitness number by using the gender-dependent equation below. The correlation between the model and true fitness number is almost linear.
Men: VO2peak = 24.24 + (0.599 x treadmill inclination in %) + (3.197 x treadmill velocity in km/h)–(0.122 x body weight in kilos)–(0.126 x age in years)
Women: VO2peak = 17.21 + (0.582 x treadmill inclination in percent) + (3.317 x treadmill velocity in km/h)–(0.116 x body weight in kilos)–(0.099 x age in years)
Non-Exercise Based Calculator: Accessible tools like the World Fitness Level calculator, based on the HUNT3 Fitness Study, can give you an estimate of your VO2 max level without you leaving your chair.
Fitness Wearables: Fitness wearables like Apple watch and Garmin also offer a VO2 max estimate based on the person’s age, heart rate, and workouts. This is not the most accurate indicator, but it does provide a consistent and continuous calculation which can make tracking progress easier.
If you have an Apple Watch Series 3 and later you can find your estimate on your health app on your iPhone under “VO2 max”.
VO2 max decreases as we age
Despite our best efforts, cardiorespiratory fitness decreases for various reasons as we age. One of the primary factors is our heart. The walls thicken, the valves stiffen, and eventually, there's atrophy. We also lose strength and muscle mass with each passing decade, our bones grow fragile, and our balance falters. Due to these changes, as well as the tendency to reduce general physical activity as we age, we lose about 10% of our VO2 capacity each decade. That’s why activities that used to be easy in our 20s and 30s (like how I ran a half marathon one day without training) gets much harder as we get older (there is no way I would ever do that now, it hurts to think about it). If you are inactive, the rate of decline is even faster. According to a study by NERF, among physically inactive persons, the average decline in fitness was 15% in ten years. Source.
Because our VO2 max is a pretty good proxy measure of our physical capabilities, it determines what we can and can’t do. The lower it goes, the less you can do. For example, for an average 45 to 55 year-old to climb a flight of stairs briskly, it would require a minimum VO2 max of about 32. But at age 75 climbing that same flight of stairs would demand the VO2 max of an elite athlete of that age. As Dr. Peter Attia puts it, “this helps explain why so many people in their marginal decade are miserable - they simply can’t do much of anything.”
Knowing and monitoring your VO2 max is crucial. You may already have a regimented workout program that you adhere to; you may be a Pilates princess that can school an NFL player on the reformer, you may be training to compete in a half marathon (please train…), or you may be part of the 25% of US adults that don’t exercise at all. Regardless of where you are in your fitness journey, I would wager that you will benefit from thinking about what you’d like to do in the later decades of your life and by using VO2 max as a yard stick to measure your progress. In other words, if you are planning on doing certain physical tasks in your golden years, you need to be training for the Centenarian Decathlon.
The Centenarian Decathlon
Coined by Dr. Peter Attia, the Centenarian Decathlon is a goal-oriented framework to train for the later decades of your life. Think of the 10 most important physical tasks you would like to be able to do for the rest of your life. This will create a template for your training.
For example, in my 8th, 9th and maybe even 10th decade, I would like to:
Hike 1.5 miles on hilly terrain
Get up off the floor using my own power
Climb a flight of stairs
Carry grocery bags to the car
Pick up a bag or small child off the floor
Touch my toes
Pull my own luggage
Swim for 10 minutes in the ocean
Balance on one leg for 30 seconds
Open a jar
These may seem like easy tasks now, but later in life, these could become impossible without preparation. Write down some of yours. What do you imagine yourself doing when you are in the later decades of your life? Great, now let’s make it real and do some math!
Some of the items I wrote involve more strength than cardio fitness. That is also incredibly important, and I will cover that in another blog post. But for now, let’s focus on what I wrote down for #1 - hike 1.5 miles on hilly terrain. In order to do that comfortably, it requires a VO2 max of roughly 30 ml/kg/min. Now, let’s take my latest VO2 max of 38. I am good to excellent for my age range and gender, but lets calculate what will happen at a 10% decline each decade of my life.
In my 40s my VO2 max will be approximately 34.2 ml/kg/min
My 50’s: it will be 30.8 ml/kg/min
My 60’s: 27.7 ml/kg/min
My 70’s: 25 ml/kg/min
My 80’s: 22.5 ml/kg/min
My 90’s: 20.3 ml/kg/min
I can probably pull it off for the next couple of decades, but at this rate I won’t be able to hike when I am in my 60s! I would need a VO2 max in the high 40s right now if I want to be able to hike in my retirement years.
Maybe hiking isn’t your thing, but remember that increasing your VO2 max by any amount is going to improve your life, not only in terms of how long you live but how well you live. “Once VO2 max drops below 18 in men and 15 and women, it begins to threaten your ability to live on your own”, says Dr. Peter Attia. “Improving your VO2 max from the very bottom quartile to the quartile above is associated with an almost 50% reduction in all-cause mortality.”
Personally, I want to increase my VO2 max from 38 to high 40s. It is an ambitious goal, yes, but not out of reach. There are ways to train and improve VO2 max, and for me it means not necessarily exercising more but shifting how I exercise.
Improving your VO2 max
The way to train VO2 max is pretty similar to the way athletes do it: by supplementing cardio and strength workouts with one or two VO2 max workouts a week. It is a high intensity interval workout, with a twist. The gold standard is the Norwegian 4x4 interval training: four minutes of intense activity at 85-95% of peak heart rate, followed by three minutes of active recovery at 60%-75% peak heart rate, repeated four times. If you don’t know your peak heart rate, you can estimate it by subtracting your age from 220.
I like to do this workout on my Peloton bike at home, but it can easily be done on a treadmill, rowing machine, or outdoors. The most important thing is to be able to control the intensity and time of intensity during the workout. I start with a warm up on my bike, and then begin the first 4 minute interval at 85% of my peak heart rate. It feels like I am close to going all out, but not quite. Four minutes ticks by slowly at that pace but the active recovery does eventually come. I still pedal during the 4 minute recovery, but I am trying to get my heart rate down to 100 beats per minute. Then I repeat the process three more times, and by the end I am sweaty and gassed.
I like to keep track of all my weekly workouts, my VO2 progress, and other health metrics so I can get an objective view of my health and fitness (as opposed to how I think I’m doing). I have created this comprehensive health and fitness template so anyone can download and use to track their goals.
Advice for novices
Novices might find starting an interval training regimen intimidating. However, Dr. Gibala, an exercise scientist, explains that beginning with an alternating pattern can help, and then gradually progressing based on individual fitness levels and goals. He suggested starting out by walking fast for a few light posts and then backing it off. Thats a form of interval training. Don’t worry at all about whether you’re at 80 percent.
Whether you're an athlete, relatively sedentary, or striving for time-efficient VO2 max optimization, interval training offers adaptable strategies to suit diverse objectives.
Conclusion
There are some things that will just happen to us as we live our lives, such as the natural and precipitous decline in strength and aerobic capacity, but that doesn’t mean that we have to let it dictate how we spend our last decades. I've seen my parents and my friends' parents age. I know that my daily choices will influence whether I'm rocking a marathon or just rocking in a chair. I’m maximizing my training to armor myself for the inevitability of aging, and the trick is to stop being a one-dimensional athlete, or aimlessly exercising. I need to be training to be an athlete of life.
References:
The HUNT3 and HUNT4 Fitness studies
Garmin, What’s a good VO2 Max for Me?
The Longevity & Brain Benefits of Vigorous Exercise | Dr. Rhonda Patrick
Outlive, Dr. Peter Attia