Running Economy: The Hidden Performance Factor That Trumps VO2 Max

Two elite runners toe the starting line of a 10K race.

Both have VO2 max values hovering around 70 ml/kg/min, virtually identical aerobic engines.

Yet one will cross the finish line three minutes ahead of the other.

The difference? Running economy.

And if you’ve been stuck at the same race times despite logging consistent miles, you’re about to discover why your VO2 max obsession might be holding you back from understanding what actually determines performance.

Why does this matter? Research demonstrates [1] that running economy can vary by up to 30% among runners with similar aerobic capacity, a difference that translates to finishing 15-30 minutes apart in a marathon despite having the same “fitness level” on paper.

First, we’ll demystify what running economy actually measures and why it trumps VO2 max as a performance predictor. Then, we’ll explore the metabolic, biomechanical, and neuromuscular factors that determine your efficiency. Finally, we’ll dig into the evidence-based training strategies,  plyometrics, strength work, and environmental adaptations, that actually move the needle.

The VO2 Max Myth That’s Limiting Your Performance

You’ve probably heard it a thousand times: “Boost your VO2 max, run faster.”

Here’s what the fitness industry doesn’t tell you: VO2 max plateaus after about 18 months of consistent training.

That’s it.

Once you’re there, you’re pretty much done improving your aerobic engine through traditional endurance training.

So why are elite runners still getting faster year after year?

Running economy.

What Running Economy Actually Measures (And Why It Matters More)

Running economy is the oxygen cost required to run at a specific pace.

Think of it as your body’s miles-per-gallon rating.

Two runners at the same pace, one burns 200 ml of oxygen per kilogram per kilometer, the other burns 220.

That 10% difference? It’s the difference between a 3:00 and 3:18 marathon.

A comprehensive review published in Sports Medicine-Open [1] defines running economy as “the integrated composite of metabolic, cardiorespiratory, biomechanical and neuromuscular characteristics.”

Simply put: how efficiently your body converts oxygen into forward motion.

Laboratory testing measures this by having you run on a treadmill at progressively faster paces while wearing a mask that analyzes your oxygen consumption.

Elite runners typically clock in at 180-200 ml O2/kg/km.

Recreational runners? Often 220+ ml O2/kg/km at the same pace.

Now here’s where it gets interesting.

Research on elite athletes [2] identified the most economical distance runner ever measured: he could run 1500m in 3:35 with a VO2 max of only 63 ml/kg/min.

For context, that’s an aerobic capacity most recreational runners could achieve with consistent training.

His secret? Exceptional running economy compensating for modest aerobic capacity.

The Performance Data That Changes Everything

Let’s look at what the research actually shows about VO2 max versus running economy.

One study [3] found that velocity at VO2 max, which combines both running economy and aerobic capacity, accounts for 94% of the performance variance in 16K time trials.

VO2 max alone? Only about 66% among mixed-ability runners.

And among similarly-trained runners, that correlation drops even further.

Another investigation [4] compared two groups of elite 10K runners with identical finishing times.

One group had 13% lower VO2 max values than the other.

How did they run the same time with inferior aerobic engines?

Their running economy was 8% better.

They simply burned less oxygen at race pace.

The bottom line? Among trained runners, running economy is a better predictor of performance than VO2 max.

The Multifactorial Nature of Running Economy

Running economy isn’t determined by one magic factor.

It’s the product of your metabolic efficiency, biomechanical effectiveness, neuromuscular power, and even your anatomy.

Let’s break down what actually matters.

Your Metabolic Engine

Mitochondrial density determines how efficiently your muscle cells produce energy.

More mitochondria = more aerobic power with less oxygen.

Muscle fiber type composition plays a role too.

Higher percentages of slow-twitch fibers generally correlate with better economy, though the research here is mixed.

Your body’s ability to use fat for fuel at higher intensities preserves glycogen and reduces oxygen demand.

The Biomechanics That Actually Matter

Here’s where things get interesting, and controversial.

A systematic review [5] analyzing 51 studies found that higher stride frequency was weakly but significantly associated with better running economy (r = -0.20).

Translation: slightly quicker, shorter steps use less oxygen than overstriding.

Studies comparing elite and good distance runners [6] showed that better economy was associated with less vertical oscillation, meaning less “bounce” in your stride.

Elite runners also demonstrated greater hip extension during push-off and more acute knee angles during the swing phase.

Ground contact time matters, but not how you might think.

Shorter contact times only improve economy if you maintain stride frequency, landing and popping off the ground quickly while keeping your cadence steady.

Now, about that forefoot versus heel strike debate everyone obsesses over.

Research by Gruber et al. [7] studied 37 habitual forefoot and rearfoot strikers.

No difference in oxygen consumption between the groups.

But here’s what did matter: when runners switched from their natural footstrike pattern, their oxygen cost jumped by 5.5%.

The takeaway? Your body has self-optimized to your natural footstrike pattern.

Changing it to match some guru’s “ideal form” will make you less efficient, not more.

The Achilles Tendon: Your Built-In Spring System

Your Achilles tendon acts like a spring, storing and releasing elastic energy with every stride.

Research indicates [8] that the Achilles contributes 50-75% of the positive work during running.

That’s not a typo, up to three-quarters of your propulsion comes from elastic recoil, not muscular contraction.

A study on elite middle and long-distance runners found a remarkable correlation (r = 0.90) between Achilles tendon moment arm length and running economy.

Shorter moment arms allowed greater elastic energy storage and return.

Unfortunately, you can’t change your Achilles anatomy.

But you can train the stiffness of the muscle-tendon unit through specific interventions, which we’ll get to shortly.

Evidence-Based Training to Improve Running Economy

Now we get to the practical stuff: what actually works to improve your running economy?

Let’s start with the foundation.

Consistent Running Volume: The Non-Negotiable Foundation

Simply running more improves economy through neuromuscular adaptations.

Your nervous system learns to recruit muscle fibers more efficiently, your tendons adapt to store and return more energy, and your movement patterns become more refined.

Research on elite runners shows economy improvements of 1-2% annually with consistent, high-volume training.

That might not sound like much, but compound that over 5-10 years and you’re looking at 10-20% total improvement.

Paula Radcliffe, former marathon world record holder, improved her running economy by approximately 15% over her career.

She did this through years of averaging 160-220 kilometers per week.

Before you panic about those numbers, understand this: you don’t need elite mileage to see improvements.

The principle is consistency and gradual progression following the 10% rule.

But here’s the problem with only running more: it takes years, and at some point you hit diminishing returns or injury thresholds.

That’s where supplemental training comes in.

Plyometrics: The Most Evidence-Based Intervention

Plyometric training has the strongest research support for improving running economy.

A landmark study by Turner et al. [9] took 18 recreational runners and split them into experimental and control groups.

Both continued their regular running for six weeks.

The experimental group added plyometric training three times per week, exercises like squat jumps, bounding, and hurdle hops.

After six weeks, the plyometric group improved their running economy by 2.3% at speeds between 10:00 and 7:30 mile pace.

Their VO2 max didn’t change.

Only their efficiency improved.

Another study on highly trained middle and long-distance runners [10] found similar results after nine weeks of plyometric training added to regular running.

But here’s the most interesting finding: a recent study [11] had amateur runners perform just five minutes of daily double-legged hopping for six weeks.

That’s it, five minutes of hopping.

Running economy improved significantly at 12 and 14 km/h paces.

No injuries, no excessive fatigue, just simple daily hops.

Why do plyometrics work?

They improve your stretch-shortening cycle, the rapid eccentric-to-concentric muscle action that happens with every footstrike.

They increase muscle and tendon stiffness, allowing better elastic energy storage and return.

They enhance the rate of force development, meaning you can generate the same propulsive force in less time with less muscular effort.

How to implement plyometrics:

Start with two sessions per week on non-consecutive days.

Build a base of general strength first, if you haven’t been doing lunges, squats, and basic bodyweight exercises, you’re not ready for plyometrics yet.

Begin with low-intensity movements like squat jumps and progresses to more demanding exercises like single-leg bounds and depth jumps.

Keep sessions short, 10-20 minutes is sufficient.

Focus on quick, reactive ground contacts rather than height or distance.

Perform plyometrics when fresh, typically after easy runs or on separate days from hard workouts.

Heavy Strength Training: The Complementary Approach

A systematic review [12] comparing heavy resistance training to plyometric training found both produce significant running economy improvements.

The strength training effect size was -0.32—small but meaningful.

One 14-week resistance intervention produced a 7% increase in plantar flexor strength, 16% increase in tendon stiffness, and 4% reduction in oxygen consumption [13].

The key is training heavy (above 85% of one-rep max) with explosive intent.

This builds maximal strength and rate of force development without causing the hypertrophy that would add dead weight.

Two weekly sessions focusing on posterior chain exercises, squats, deadlifts, Romanian deadlifts, calf raises, and single-leg work, provide sufficient stimulus.

Schedule strength training on the same days as your hard running workouts to maximize recovery days.

Environmental Adaptations: Altitude and Heat

Altitude training improves running economy through metabolic adaptations in skeletal muscle.

A 10-day altitude training camp study [14] at 1,828 meters showed running economy improved from 61.30 to 56.44 ml O2/kg/min.

That’s an 8% improvement in just 10 days.

The “live high, train low” protocol works best, sleep at altitude where your body produces more red blood cells, but train at lower elevations where you can maintain workout quality.

Unfortunately, most of us don’t live near mountains or have access to altitude houses.

Enter heat training.

Research by Lorenzo et al. [15] demonstrated that 10 days of heat acclimation (60 minutes of moderate-intensity cycling in 40°C) improved performance in cool conditions.

Plasma volume increased by 6.5%, cardiac output improved by 9.1%, and exercise economy enhanced significantly.

The mechanism? Heat stress triggers similar cellular adaptations as hypoxia, specifically increased heat shock proteins that protect cells from stress.

Heat training is accessible to every runner.

Throw on extra layers during easy runs, train during the hottest part of summer days (carefully and properly hydrated), or use a sauna post-workout.

Five to ten days of heat exposure can produce measurable adaptations.

Putting It All Together: Your Running Economy Action Plan

Here’s how to actually implement this information based on your current training level.

If you’re a recreational runner (30-40 miles per week):

Focus on consistent volume progression first.

Add two 15-minute plyometric sessions per week after easy runs.

Start simple with squat jumps, skipping, and light bounding.

If you’re an experienced runner (40-60+ miles per week):

Maintain your running volume as the foundation.

Add heavy strength training twice per week during base-building phases, focusing on posterior chain development.

Include plyometrics twice weekly with progressive difficulty, single-leg work, depth jumps, and reactive bounds.

Consider a 1-2 week heat acclimation block 2-3 weeks before goal races.

For everyone:

Stop obsessing over your footstrike pattern, your natural stride is probably optimal.

Track progress through pace at given heart rates rather than expensive lab testing.

Be patient, meaningful economy improvements take months to years, not weeks.

Don’t let supplemental training compromise your primary running adaptations.

The Bottom Line

Running economy explains why runners with “average” VO2 max values consistently beat athletes with superior aerobic engines.

It’s trainable throughout your entire running career, unlike VO2 max which plateaus relatively early.

The evidence-based interventions, plyometrics, heavy strength training, consistent volume, and environmental adaptations, produce small but meaningful improvements that compound over time.

A 2-4% improvement in running economy translates directly to 2-4% faster race times across all distances.

Start with one intervention this training cycle, probably plyometrics given the strength of evidence and accessibility.

Be consistent, be patient, and trust that the adaptations are happening even when progress feels invisible.

Your running economy will reveal itself on race day, when that same perceived effort carries you significantly faster than before.