Improving running economy is probably the most efficient way to shave off minutes from your 10k or (half) marathon time. At the same time, it’s an overlooked metric that is often wrongly measured. That’s why it’s time for a change! This comprehensive guide covers everything you need to know about running economy (RE): from theory to practice.

by Sebastian Weber 

VO2max testing for running economy

In addition to providing valuable insights and strategies for improving the running economy, we also encourage you to share this article with your fellow sports coaches and athletes. 

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Table of Contents


Running economy is the energy cost for a given running speed. The better your running economy, the less energy it takes to run at a certain speed.

In this definition, energy cost or energy demand is often expressed in oxygen (O2) demand.

You could for instance have an oxygen demand of 55 ml/min/kg when running 4 m/s. This equals a running economy (oxygen demand) of 229 ml/kg per kilometer.

We’ll dive a little bit deeper into the formula in a bit. But first, it’s good to know that running economy is not exactly the same as running efficiency.


To run fast, you need a certain running power. Generating this power costs energy.

  • Running efficiency only looks at the energy cost to generate power (gross efficiency). It does not look at the second step of translating this power into speed. Note that not all running power will result in running speed.
  • Running economy on the other hand, bypasses the power and directly looks at how much energy it costs to run at a certain speed.

Watch this 3 minute video to get a better understanding of the difference between running economy and efficiency:


By improving your running economy, you can easily shave off >15 minutes of your marathon time.

The interesting part is, that you don’t even need to improve your basic physiology like VO2max. That means that in most cases, you don’t need to train more or harder. Instead, you can focus on improving your running economy during your existing training hours.

Here’s an example of the effect of running economy improvements on your marathon time:

All you need is a way to measure the running economy (“you can’t improve what you don’t measure”) and a training strategy to improve RE.

Let’s continue with those two topics.



An example protocol to measure RE could include 3-4 (sub) maximal efforts of 6 minutes, at a constant running speed.

You would need to sample VO2 data in the final minutes, when VO2 reaches a steady state. For high intensities above threshold, VO2 will not reach a steady state. You could use the last 30 seconds average instead.

Write to us or schedule a 1:1 consultation in your own language if you want the detailed protocol or if you want to learn more about the running economy test.

You now have the oxygen uptake that is necessary to determine RE. However, you need to normalize the values to prevent flawed data. We’ll share how to do that in a bit, but let’s first have a look at the RE formula.


Your VO2 analyzer measures your oxygen uptake in ml/min. You can divide this by bodyweight to get ml/min/kg.

The running economy looks at VO2 uptake, depending on running speed. That’s why the most basic running economy equation is:

VO2tot (ml/min/kg) ÷ Running speed (m/s)

Another way to describe running economy is based on the required milliliters of oxygen per kilometer, normalized for bodyweight. As a result, you get an oxygen demand per kilometer (ml/kg/km):

VO2tot (ml/min/kg) * Running speed (min/km)

However, you can’t just measure VO2 uptake and running speed and get a reliable running economy result! That is because you first need to normalise for:

  1. Basal metabolic rate (basel O2 consumption)
  2. Additional oxygen demands for fat combustion
  3. Energy production by (anaerobic) glycolysis

INSCYD is a performance software tool that automatically solves these issues for you. Let’s continue to learn more about the 3 measurement flaws.


The worst thing you can do is to calculate running economy by measuring VO2 uptake and dividing it by running speed. As we mentioned in the previous section, you need to normalise VO2 measurements before you can use them.

Watch the 5-minute video to learn about the 3 measurement flaws you need to prevent or continue reading.


There is a certain amount of O2 uptake that is fixed at rest. This basal O2 uptake is not connected to running at all. Instead, this O2 level is required for simple “life-keeping” and “non-locomotive” activities such as the work of your brain and organs.

If you do not subtract this value from the overall O2 uptake, then you’ll get an incorrect running economy result. So, in order to have a precise reading of your running economy, the first correction that needs to be done is deducting the “basal” O2 consumption at rest.

Even when you calculate the running economy through a ramp-test – where speed increases steadily and you measure the corresponding O2 uptakes – the “basal” O2 consumption will weigh on the O2 uptake at different speeds with different percentages. The effect of basel O2 consumption is higher at lower speeds (because of the lower O2 uptake) and lower at higher speeds, where the O2 uptake is higher.

Fortunately, the INSCYD software automatically corrects for basal O2 consumption.


The second factor you need to normalise for is connected to another vital part of your exercise, which is the fuel you need to produce energy.

When you’re running at lower intensities, you use a significant amount of fat as fuel. Before you can burn fat, it first goes through a metabolic pathway called beta-oxidation. This pathway prepares fat to become fuel, and requires additional O2. This process is not linked to energy production for muscle contraction.

INSCYD %Fat & Carbohydrate Grapth
When you’re running at lower intensities, you use a significant amount of fat as a fuel.

You have to exclude the additional O2 consumption from beta-oxidation for your running economy analysis. That is because – as is the case for the basal O2 consumption – the additional O2 consumption from beta-oxidation is not there to produce energy for locomotion.

Here’s what often happens if you forget to do this.

A runner becomes a better endurance-trained athlete after a training program. He/she burns more fat at a given intensity. Because more fat is burned, O2 consumption increases in the beta-oxidation. For most endurance athletes, this is a good thing. However, if you forget to normalize for this additional oxygen uptake, you’ll think that running economy becomes worse every time an athlete increases fat combustion.

Be aware when your test result says: “Your fat combustion increased! But your running economy got worse..”

This problem is avoided when the running economy is determined with INSCYD, since INSCYD records and eliminates the proportion of oxygen uptake attributable to beta oxidation that is not used for muscle contraction.


The first two measurement flaws have a high impact on your running economy reading at low intensities. This one impacts your outcome at higher intensities.

With increasing speeds, an increasing amount of energy is derived from anaerobic metabolism (glycolysis). This energy system produces energy without the need for O2.

You can’t measure this energy production with oxygen uptake. As a result, if you only measure oxygen uptake, you underestimate the energy required to run at a certain speed.

Energy contribution percentage aerobic and anaerobic
The anaerobic energy contribution increases when running power increases.

Here’s what happens if you don’t take this into account.

Imagine an athlete who becomes more endurance trained after a training program. As a result, the aerobic metabolism becomes more dominant at a given running speed. This will result in higher oxygen uptake rate at a given speed. If you don’t normalise for anaerobic energy production, running economy seems to decrease.

Be aware when your test result says: “Your VO2max increased! But your running economy got worse..”

This is not the case with INSCYD. 

INSCYD looks at the total energy demand, combining the aerobic and anaerobic energy production. This gives an exact picture of the running economy, which is always accurate – even if the aerobic vs. anaerobic energy distribution has changed (e.g. due to training).


INSCYD takes basal rate, fat combustion and anaerobic metabolism into account when measuring running economy. It’s the only software available to do so.

“INSCYD offers us the ability to create the most accurate measures of metabolic efficiency available today.” — PROF. DR ELLIOT W. HAWKES – STANFORD UNIVERSITY

If you are a coach or represent a lab, book a free 1:1 demo in your language with an INSCYD expert to learn more about how it can help improve your athletes’ running performance and receive tailored advice for enhancement. Athletes can also find their INSCYD coach or lab.


There are several training strategies that have the potential to improve running economy. Although there is some scientific literature, not all studies normalise for the 3 factors we just discussed.

In literature, there’s often no consensus yet whether a certain training plan improved running economy. Which could simply be due to the fact that it is not always measured the right way.

However, you don’t have to wait for science to reach consensus or find statistical significance. Instead, you can test it yourself. Remember that INSCYD allows you to individually test whether training methods improve your RE.

Here’s a short list of the strategies that can improve running economy.


As mentioned in the beginning of this article, running economy can be improved without the need to train more or harder.

The easiest way to do that is by improving running technique during the existing running workouts.

This study found that numerous technique variables correlate with RE. Examples of variables that they looked at:

  • Vertical oscillation
  • Braking (change in velocity during ground contact)
  • Posture
  • Stride parameters (e.g. stride length, cadence, ground contact time)
  • Lower limb angles (e.g. hip, knee and ankle joint angles)

The scientific outcomes, together with a technique analysis can be a good first step to improve running technique and therefore running economy.

Analysing running technique using the LEOMO LVS System


Endurance training increases VO2max, but does it also increase RE? This study shows that there is a positive relationship between VO2max and running economy.

Moreover, they found a positive relationship between changes in running economy and VO2max. This suggests that increasing VO2max with endurance training will increase RE as well.

Besides an increase in VO2max, endurance training also simply increases training volume and running experience. You would expect a higher RE in trained runners vs untrained runners. Indeed, the number of years of running experience has been suggested to be important to RE.

This process takes time. So you’re probably interested in whether you can speed up the process. Let’s continue.


High-intensity training – or interval training in general – enables you to accumulate more time at a race pace. This review suggests that runners are typically most economical at the running velocities at which they habitually train.

These two findings combined suggest that it makes sense to implement HIT training with race pace intervals.

With regular INSCYD tests, you can double-check if a HIT training plan with interval workouts improves your personal RE.


Resistance training can improve running economy in several ways. For instance: by improving muscle coordination, leg and tendon stiffness, neuromuscular recruitment, biomechanical efficiency, etc.

Initial performance gains are a result of neuromuscular adaptations. Only in time, muscle adaptations can be expected.

Running Economy explained
3 athletes with the same VO2max run at the same intensity. Due to a difference in running economy, their time on a marathon can differ up to 30 minutes (!).

Both heavy resistance- and “endurance” resistance training are shown to be effective.

Another type of resistance training that is shown to be effective is plyometric training. This is an explosive type of resistance training that is more running movement specific. It aims to increase the stiffness of the muscle-tendon system.

So far, plyometric training is not shown to be superior to traditional resistance training, when it comes to improving running economy.

However, movement specific resistance training is shown to be effective in other sports. When translated to running, uphill running could also be a way to make resistance training movement specific.

Great news for you! INSCYD College is the ultimate resource to help you or your athletes unlock full potential. Don’t miss this opportunity join to elevate sports performance to new heights


Now that you know what running economy can do for you, it’s time to improve it.

  1. Start with a running economy test.

    Find out whether RE is something you should work on and set a baseline.

    Labs and coaches should make sure they normalise for the 3 factors that otherwise would mess up the reading. The easiest way to do that is by using the INSCYD athletic performance software! Schedule a free demo to start using INSCYD.

    Athletes can make sure their economy is measured the right way by doing a test with an INSCYD coach or lab. You can find them here.

  2. Improve your running economy.

    You can start with (one of) the suggested methods: technique training, endurance and HIT training, strength training.

  3. Track progress.

    Don’t waste precious time trying to improve your economy, only to find out it didn’t have a positive effect (or worse). Track RE progress over time, to learn what works, and what doesn’t.

If you found this guide helpful, don’t forget to share it with your fellow coaches and athletes! Click on the social media buttons below to spread the word and help others improve their running economy.

Sebastian Weber
Sebastian Weber

Sebastian Weber, has been head coach in professional endurance sports more then 12 year. After his studies of Sport Science and Molecular Human Biology, Sebastian ran several research projects on muscular energy metabolism and its adaptation to training. Since 2015 Sebastian works as a performance consultant for several national federations in cycling, triathlon, swimming, skiing and more.