Running: Maximum Aerobic Capacity (VO₂ Max)

Distance running is an activity that relies heavily on the ability of the lungs and heart to supply oxygen to skeletal muscles in order to produce energy. In theory, the more oxygen a runner is able to provide working muscles the more effectively they should be able to perform.

The maximum rate at which an individual consumes oxygen during incremental exercise is termed VO₂ Max or maximum aerobic capacity. This is a measure of aerobic fitness and is associated with success in endurance sports.¹

What is the VO₂ Max of high level distance runners?
High VO₂ Max values are associated with elite endurance performance. Maximum aerobic capacity values of elite distance runners have been reported to be between:²

• 60-85 mL/kg/min in men and 55-72 mL/kg/min in women

As a reference it is not unusual for untrained individuals to have values between:

• 38-52 mL/kg/min in men and 30-46 mL/kg/min in women.

A high VO₂ Max does not always equal running success. Other physical/physiologic factors such as running economy and velocity at lactate threshold are also extremely important.

How can VO₂ Max be determined?
Incremental exercise testing in a lab setting would be the gold standard but several field tests have been proposed.  One field test which gives a good estimate of Vo2 max in athletes and would be specific to running is the 12 minute run test.³

Materials

• Running track although a treadmill with a 1% grade may be acceptable
• Measuring tools to help determine distance
• Timer

Testing

• Warm up.  Make sure the warm-up is the same each time you test to ensure you can accurately assess improvements.  A sample warm up could be to perform a 5 minute easy run, 7 minutes of light stretching and 3 minutes of a more vigorous jog.
• Run as far as possible for 12 minutes.  It is permissible to walk if needed.
• Record distance covered in meters. 

VO₂ Max = (meters covered in 12 minutes – 504.9)/44.73 = (___)mL/kg/min

To help set training intensity it can be useful to have an estimate of velocity at VO₂ Max (vVO₂ Max).  The vVO₂ Max is the minimum running velocity at which VO₂ Max occurs. This is a measure of distance/time (km/h) and an can be calculated as follows:⁴

vVO₂ Max = VO₂ Max/3.5

vVO₂ Max can typically be sustained for ~6 minutes. With this in mind another way to estimate vVO₂ Max may be to determine maximum distance covered during a 6 minute time trial and convert to km/h.

Improving VO₂ Max 
Once the runner has an idea of what their cardiorespiratory fitness is they may decide that it needs to be improved to become a more competitive runner. In order to improve VO₂ Max the cardiorespiratory system must be adequately taxed. This is a much easier task in the novice than in the elite runner.

The following scale may be useful to determine training intensity:⁵

Very Light to Fairly Light: 25-44% VO₂ Max
Fairly Light to Somewhat Hard: 45-59% VO₂ Max | Notice breathing deeper but conversation possible |
Somewhat Hard to Hard: 60-84% VO₂ Max | More difficult to hold conversation |
Very hard: 85% VO₂ Max | Harder breathing and becoming uncomfortable don’t want to talk |
Maximal: 100% VO₂

Novice Runners ^6,7,8
Training at intensities that are considered “moderate” in intensity (40-50%VO₂ Max) could be useful to increase maximum aerobic capacity.

Intermediate Runners ⁸
Training at intensities that are considered “hard” 60-80% of  VO₂ Max will likely enhance maximum aerobic capacity. There is potential that runners who training <60-80 km a week may be able to improve VO₂ Max by increasing training load.  Some low volume training at VO₂ Max may be beneficial.

Well Trained Runners
In well trained runners training at or near VO₂ Max is probably optimal. This type of training can be stressful and should be periodized and is not appropriate for everyday runs. A sample periodized training plan has been proposed by Midgley et al.

• Perform several months of base training at 65-70% VO₂Max
• A transition phase of around 85% VO₂ Max would then be implemented
• Targeted VO₂ Max training would begin after base training and the transition phase

Midgley et al. suggests that the targeted VO₂ Max training increase in intensity from midway between velocity at lactate threshold (vLT) and vVO₂ Max then eventually progress training to levels that exceeds vVO₂ Max. I have described how to estimate the velocity at lactate threshold in another article and how to estimate vVO₂ Max in the testing section of this article.

Training at or close to vVO₂ Max can typically only be sustained for ~6 minutes so interval training may be valuable to increase the actual time at vVO₂ Max during a training session. 

Elite runners may need to assess whether they even need to try to improve VO₂ Max. Many of these runners may have hit their ceiling after many years of training.

Bottom Line
Maximum aerobic capacity is associated with running performance and can be trained. As a runner becomes progressively more experienced increased training intensity will likely need to be employed. Care must be taken not to over train.

References

1. Midgley, Adrian W., Lars R. McNaughton, and Andrew M. Jones. “Training to enhance the physiological determinants of long-distance running performance.”Sports Medicine 37.10 (2007): 857-880.
2. Physiological Testing of the High-Performance Athlete
3. O’GORMAN, D. O. N. A. L., et al. “Validity of field tests for evaluating endurance capacity in competitive and international-level sports participants.”The Journal of Strength & Conditioning Research 14.1 (2000): 62-67.
4.  Léger, L., and D. Mercier. “Gross energy cost of horizontal treadmill and track running.” Sports medicine 1.4 (1984): 270-277.The gold standard measure of cardiorespiratory fitness is called maximum aerobic capacity or VO2 max.
5. http://www.move.va.gov/download/Resources/CHPPM_How_To_Write_And_Exercise_Prescription.pdf
6. Branch, J. David, Russell R. Pate, and Sharon P. Bourque. “Moderate intensity exercise training improves cardiorespiratory fitness in women.” Journal of women’s health & gender-based medicine 9.1 (2000): 65-73.
7.Poole, David Christopher, and GLENN A. GAESSER. Response of ventilatory and lactate thresholds to continuous and interval training. MS thesis. UCLA, 1984.
8. Midgley, Adrian W., Lars R. McNaughton, and Michael Wilkinson. “Is there an Optimal Training Intensity for Enhancing the Maximal Oxygen Uptake of Distance Runners?.” Sports Medicine 36.2 (2006): 117-132.