Is VO₂ Max Overrated? The Truth About Endurance Performance

VO₂ Max vs. Efficiency: Why One Number Doesn’t Tell the Whole Story

When most people hear VO₂ max, they think it’s the ultimate measure of endurance. And while it's an important metric, focusing on VO₂ max alone can be misleading. If your goal is to get faster, go longer, and recover quicker, it's time to look beyond just that one number.

What Is VO₂ Max and Why Does It Matter?

VO₂ max is your body’s maximum ability to take in and use oxygen during intense exercise. It reflects how well your heart, lungs, and muscles work together under stress.

Think of it like your engine size. A bigger engine has more power potential. The more oxygen (fuel) you can use, the more work you can theoretically perform.

But here's the catch: power isn’t everything.

If you're not efficient if you're wasting energy. If you're wasting energy you're not getting the most out of that engine. A high VO₂ max gives you capacity, but performance depends on how well you use that capacity.

VO2 Max & Muscle Oxygen Kinetics data capture

Why Efficiency Deserves Equal (or More) Attention

Efficiency, also called movement economy, is how much oxygen you use to maintain a given pace. If two runners are cruising at the same speed but one uses less oxygen, that runner is more efficient. They fatigue slower. They recover faster. And they often outperform others even with a lower VO₂ max.

How Much Can You Improve Each?

Let’s uncover exactly where you can improve and show you how much more you stand to gain when you do.

VO₂ Max

• Increases by about 10–20% with consistent aerobic training

• Beginners may improve more; elite athletes typically see only 3–7%

Efficiency

• Can improve 10–30% over time

• Gains come from better biomechanics, strength work, mobility training, and sport-specific practice

Which One Delivers More Performance Gains?

This is where it gets interesting.

Let’s imagine you improve both your VO₂ max and your efficiency by just 5%. On paper, the numbers may look similar, but in practice, the gains tell a very different story.

A 5% boost in VO₂ max gives you a slight uptick in aerobic capacity. That’s great, but it often translates to only about a 1–2% improvement in performance. Think of it like raising the ceiling on your potential without necessarily using it more effectively.

Now, contrast that with a 5% gain in efficiency. Here, you’re doing the same work while using 5% less oxygen. That’s a game-changer, especially in longer efforts, often resulting in a 2.5–5% performance improvement.

Here’s what that looks like in the real world: imagine a runner who currently finishes a 10K in 40 minutes. With a VO₂ max increase, they might clock in between 39:12 and 39:30. But with improved efficiency? They’re likely looking at 38:00 to 39:00, with no extra effort required.

Same effort. Better results.

What the Research Shows

And the science backs this up.

A landmark study by Saunders et al. (2004) showed that a mere 1% improvement in running economy typically leads to a 1% faster race time, a near one-to-one return. Joyner and Coyle (2008) took it further, noting that at higher levels of VO₂ max, it’s not about how much you have, but how effectively you use it.

In elite endurance sports, the true differentiator isn’t just aerobic capacity, it’s movement economy. That’s what often separates the podium finishers from everyone else chasing them.

Should You Still Train VO₂ Max?

Absolutely. VO₂ max still matters for both performance and long-term health.

A 2018 JAMA study found that people with higher VO₂ max levels had significantly lower risk of early death. In fact, going from low to average fitness cut mortality risk in half. But if your goal is to move better, feel stronger, and sustain effort, efficiency is where the biggest performance gains come from.

How to Measure and Improve Both

To unlock your full potential, use a data-driven approach.

Step 1: Get Tested (We Can Help at ISHP)

• VO₂ max test: Measures your aerobic capacity

• Lactate, ventilatory, or NIRS threshold tests: Show how close you can perform to that capacity

• Movement economy analysis: Reveals how efficiently you move

Step 2: Train Smarter

• Combine aerobic training with strength and mobility

• Focus on form and movement economy during every session

• Practice sport-specific skills regularly and intentionally

The Bottom Line

• VO₂ max sets your upper limit

• Efficiency determines how close you can get to that limit without burning out

The best athletes (and the healthiest people) train both.

Ready to revolutionize your training, perform better, and achieve new levels of endurance?

Get tested. Train with intention. Transform your performance. Let us show you how.