VO₂ Max: The Holy Grail Of Health Metrics
VO₂ max is on par with smoking, hypertension, and type 2 diabetes when it comes to predicting your overall lifespan. How can you reap the rewards of optimizing it?
During my D1 baseball career, we had conditioning built into our program.
And for the three and a half years I played, I hated every minute of it.
I would dread Tuesdays and Thursdays when they arrived:
110 yard sprints (we ran 16 sprints with 16 seconds of rest between each one)
Uphill lunges (I swear the hill had a 60-degree incline)
Shuttle runs on the warning track (while we inhaled the dust others kicked up)
Simply put: it wasn't my cup of tea.
Once my playing career came to an end, I took advantage of my newfound freedom.
I completely abandoned the cardio I hated doing.
It took two years before I realized I had made a mistake.
I picked up hypertrophy & strength training for the vanity.
But overlooked the importance of cardio for longevity.
This realization has caused my view on health & fitness to completely 180.
I've got several running theories for how and why my perspective shifted:
Is it a result of maturity? Can I understand things now that I couldn't internalize at the ages 18-22?
Has completing a major stage in my life (graduate school) made me more aware of the passing time, and by extension, my own mortality?
Was it born out of my quest to seek a better day-to-day quality of life?
Have my in-depth studies of Bitcoin shown me the benefits of a longer time preference? (This topic could fill an entire newsletter by itself)
Whatever the cause, theres one thing that's certain — I'm a data-driven person.
I began scouring the internet for information that could help me answer the question:
What are the best metrics I can use to track and optimize my long-term health?
Through my research, I landed on the gold standard of health metrics: VO₂ max.
What is it?
VO₂ max is the maximum rate your body can utilize oxygen during exercise.
It's measured as the milliliters of oxygen used in one minute (per kg of body weight).
Essentially, it measures how quickly you can:
- intake oxygen into your lungs
- channel it into your blood
- distribute it to your muscles
- utilize the oxygen in metabolic processes to create ATP (energy)
So what is the VO₂ max metric actually indicative of?
It measures how efficiently your body can convert oxygen into energy — specifically, the body's limit for producing aerobic energy.
It's important to recognize that despite reaching the point of peak oxygen utilization, you'll still be able to continue increasing intensity.
How?
You'll begin to tap into other forms of eneergy production, such as starting to use other forms of energy through your anaerobic system.
As a result, VO₂ max isn't able to tell you what your maxium exertion is, but it can give you an understanding of your aerobic engine.
Why is it important?
While genetics account for about 20-40% of the variability in VO₂ max amongst the population, the evidence is overwhelmingly clear:
You can increase your VO₂ max through targeted training.
But why would increasing your bodies ability to utilize oxygen be beneficial to you?
As illustrated above, VO₂ max measures the combined efficiency of multiple bodily systems:
Respiratory System - Lungs
Cardiovascular System - Heart & Veins
Muscular System - Muscles
As a result, VO₂ max is often used as a measure of an individuals cardiorespiratory fitness.
Here's when we know:
The American Heart Association has established that low cardiorespiratory fitness (and thus low VO₂ max) is associated with a higher risk of cardiovascular disease, cancer, and all-cause mortality.
Cardiorespiratory fitness can also be seen as a strong predictor of mortality, alongside cigarette smoking, hypertension, and type 2 diabetes.
The takeaway?
We want our VO₂ max to be as high as possible.
But there's a problem:
As you might expect, our cardiorespiratory fitness and VO₂ max fall naturally as we age.
According to the literature, the average person's VO₂ max will drop by:
1% per year after you turn twenty (10% per decade)
1.5% per year after you turn fifty (15% per decade)
These rates of decline might not seem like a lot.
But compounded over time, this decline leads to drastic differences in quality of life:
The above chart illustrates the decline in VO₂ max for individuals with low, average, and elite levels.
The dotted lines indicate the required VO₂ max score to complete each respective activity.
As we can see from the chart:
a person with an average VO₂ max will lose the ability to walk up stairs around the age of 50 years old (using solely aerobic energy)
a person with an elite VO₂ max won't lose this ability until they are around 75 years old
To combat the effects of aging, you can train to improve your VO₂ max.
By achieving higher levels through training, you can better prepare yourself for the decline you'll inevitably be faced with.
A high VO₂ max won’t just increase the quality of life you experience, it’ll increase the length of your life too.
The above chart divides VO₂ max scores into performance buckets by age and sex.
Going from zero exercise to an average VO₂ max results in a 50% reduction in premature death for the average person.
It doesn't stop there.
On average, if you're able to train your way into the high or elite VO₂ max category, you'll reduce your risk of premature death by 4-5 times.
How To Improve
By now, you're probably convinced that training to optimize your VO₂ max is worthwhile.
So what's the best way to train?
According to Dr. Peter Attia, you want:
80% of your training volume in zone 2
20% of your training volume in zone 5
You might ask why the volume is divided so unevenly.
Here's the reasoning:
You'll spend the majority of your training time in your zone 2 to build a large aerobic foundation (your VO₂ max is reflective of your aerobic efficiency after all).
This zone is less physically demanding, allowing you to perform large amounts of volume before recovery and fatigue become issues.
While in zone 5, you'll push the limits of your aerobic system AND stress your anaerobic (glycolytic) energy production system.
Unlike zone 2 workouts, zone 5 provides an extremely intense and acute stimulus on your body.
Because of this, you can only stay in this zone for so long until overtraining becomes an issue.
Dr. Peter Attia uses the analogy of maximizing the area of a triangle.
To maximize the area (VO₂ max):
we need a wide base (zone 2)
we need a high peak (zone 5)
But what does the actual training within each of these two zones look like?
Let's start with zone 2:
When you train in this zone, you should be aiming to sit at an RPE (rate of perceived exertion) that allows you to maintain a conversation with another person.
While you should be able to speak, it should be mildly difficult to (you shouldn't want to).
Dr. Peter Attia refers to it as "the all-day pace" and recommends that people spend around 4 hours a week, split into 3 total sessions in this zone.
You can perform this training in any of the following ways:
Brisk Walking
Slow Jogging/Running
Cycling
Swimming
Rowing
Elliptical Trainer
Hiking
As long as you're able to keep a steady pace that allows you to maintain the same level of intensity for an extended period of time, you're good to go.
There is no real upper boundary to the amount of zone 2 training that you should do.
The upper limit is dependent on the following:
how much free time you have during your week to allot to it
whether your body can handle the workload
Now that you've got an idea of zone 2 training, what should your zone 5 training look like?
This post by Dan Go nails it.
By performing an activity of such high intensity that you can only maintain that pace for about 4 minutes, you'll need roughly an equivalent recovery time.
Dan is cites research studies that confirm performing this style of zone 5 workout once a week is enough to see continued improvement.
This matches Dr. Peter Attia's recommendation of a single session a week performed for about 30 minutes.
While sprinting is a great option when it comes to training in zone 5, it's far from the only option.
Here's a bunch more to consider:
Cycling
Stair Climbing
Swimming Sprints
Hill Repeats
As long as you adhere to the guidelines above, you'll be training optimally for improving VO₂ max.
How To Track It
Lastly, if you're going to do the work to improve your VO₂ max, you're going to want a way to track your progress.
In a clinical setting, you’d use a specialized face mask to measure the volume of oxygen and carbon dioxide in your breath at peak aerobic capacity to determine your VO₂ max.
But there's an issue:
Most of us don't have ready access to equipment of this kind.
So what are our other options?
Fitness Trackers
Modern fitness trackers can use advanced algorithms based on heart rate data, activity level, and sometimes other physiological markers to estimate your VO₂ max.
Devices like Fitbit, Apple Watch, and Garmin provide convenience and continuous monitoring, making them a great tool for tracking trends and relative changes over time.
However, these devices have some limitations:
Incompatibility Across Models - comparison across different fitness trackers may be difficult because of variance in their algorithms (which can lead to inconsistencies in VO₂ max estimates)
Heart Rate Accuracy - the accuracy of the heart rate monitor can significantly impact the VO₂ max estimate (factors like temperature, altitude, and hydration can affect heart rate and, consequently, VO₂ max estimates)
Additionally, what if your fitness tracker doesn't have this metric built into their service at all?
Personally, I'm a Whoop user and don't have access to this data.
On top of this, while I think a fitness tracker is a worthy investment, the necessity for one still represents a barrier to entry for people who don't own one.
Beep Test
The beep test, also recognized as a shuttle run test, is a field test that can be used to estimate an individual’s VO₂ max.
It involves running back and forth over a 20-meter distance at increasing speeds until exhaustion, with pace set by audio beeps.
While it still doesn’t beat measuring the actual oxygen and carbon dioxide in your breath, plugging your beep test score into to a formula allows you to approximate your VO₂ max value ― they have a 0.92 correlation.
Here's how you can conduct the test:
Place two markers down 65 feet (20m) apart.
You’ll be guided by audio beep signals, so find a way to have the audio running with you conduct the test (I use this Youtube video).
When you hear the first beep, begin sprinting over to the opposite marker.
If you reach the marker before the beep, rest until the next beep sounds, then sprint back to the other marker (all beeps on each level have the same time between them).
As you continue to progress, the audio recording will inform you that you've advanced to a new level (all the sprints at the new level will have a shorter time between them).
If you fail to reach the marker before the beep, continue sprinting until you reach the marker, then immediately turn and try to reach the opposite marker before the next beep sounds.
If you fail to reach the required marker before the beep for a second time, you’re eliminated from the test.
Record the level you were on and last completed shuttle number as your result.
Once you've completed the test, you can plug your level and last recorded shuttle number into the following formula to see what your corresponding VO₂ max is:
Utilizing a spreadsheet application like Excel or Google Sheets makes it easy to repeat this process over time.
Here's a table I made in my personal spreadsheet that shows the corresponding VO₂ max scores you achieve by mazing out each level of the beep test:
There are a number of advantages the beep test holds over fitness trackers:
Direct Measure of Endurance - the beep test measures endurance and aerobic capacity directly through physical performance (unlike algorithm fitness trackers).
Widely Validated - it is a well-researched and validated method for estimating VO₂ max.
Practical and Accessible - it requires minimal equipment and can be performed in various settings.
However, these advantages should be weighed by the potential downsides of this metric as well:
Maximal Effort Required - it requires you to exert max effort while fitness tracker do not (in reality you should be fine with this as you’re already doing so in your zone 5 training).
Motivation and Pacing - your performance can be influenced by your motivation and ability to pace yourself.
External Factors - factors like surface type, footwear, and weather conditions can affect your performance.
Overall, fitness trackers are useful for monitoring trends and relative changes in VO₂ max over time, but for a more accurate and validated assessment, the beep test or a lab-based VO₂ max test is preferable.
Ultimately, it's up to you to determine the standard of the tests you'd like to uphold.
Wrap Up
To ensure your training optimizes your VO₂ max and extends your longevity into your old age:
Do at least 3 zone 3 training sessions per week for around 4 hours total.
Do at least one zone 5 training session per week for over 30 minutes total.
Follow the instructions above when conducting these training sessions.
Track your progress using lab-testing, fitness tracker estimations, or beep test results.
Best of luck to you.
Until next time.
— Landon