VO2 Max in Fighting Cocks (Ep. 1)

VO2 Max in Fighting Cocks (Ep. 1)
By Asst. Prof. Dr. Sompoth Weerakul (Ajarn Kaew)

What is VO2 Max and why is it important in Fighting Cocks?
Very few people understand these metrics in animals, whereas among human athletes—especially those in endurance sports—it is a standard concept. This is a subject that enthusiasts of avian sports must study further to keep pace with modern sports medicine.

VO2 Max is the maximum rate of oxygen consumption that the body can utilize per kilogram of body weight per minute. Simply put, a higher value indicates superior muscular endurance; the more oxygen the body can process, the better. It is measured during peak intensity exercise up to the limit of aerobic capacity, which leads to increased stamina and strength. As explained in previous articles, energy production via the oxygen-reliant pathway (the Krebs Cycle) yields much higher energy and reduces the production of lactic acid—the "disaster" of performance.

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There is a significant gap between athletes and average individuals, which explains why they tire at different rates. A typical athlete may have a value of 60–80 ml/kg/min, but elite professionals, such as pro cyclists or ultra-trail runners, can see values exceeding 95.


Do Birds Have VO2 Max?
Extensive research exists regarding birds, and it is not a distant concept. However, many cockfighting enthusiasts may never have encountered this data. Understanding the science allows for better application in training.

For instance, a study by Patrick J. Butler (2016) published in Philosophical Transactions found that migratory birds utilize oxygen much more efficiently than resident birds. These birds possess:

Larger hearts.
Higher hemoglobin concentrations in their blood.
Denser capillary networks in their muscles.
All these factors contribute to increased oxygen delivery and a higher VO2 Max.

Studies further confirm that VO2 Max measurements in birds are just as valid as those in mammals and humans. A study by David J. Ellerby et al. (2003) published in Physiol Biochem Zool. focused on Guineafowl. Classified as "running birds," they have been studied extensively. They exhibit a remarkably high average oxygen consumption, with a VO2 Max of 97.5 ± 3.7 ml/kg/min—matching the world’s strongest human athletes. Comparisons with the Rhea (a relative of the ostrich) show that Rheas possess an even higher factorial aerobic scope.

These examples illustrate that "running birds" (like Guineafowl and Rheas) and migratory birds possess much higher oxygen efficiency than birds without such behaviors.


What About Fighting Cocks?
It is understood that both chickens and Guineafowl belong to the same order, Galliformes, making them closely related.

When a fighting cock undergoes consistent training (the methods of which I will explain later), that bird will develop greater stamina and endurance, allowing it to spar or fight longer without fatigue. This performance depends on both genetics and training techniques.

Furthermore, performance is influenced by specific nutrients related to oxygen delivery and transport. In testing, there is a clear difference between birds that receive these nutrients and those that do not. These nutrients directly enhance the body's oxygen utilization efficiency.

How can we train our fighting cocks to achieve a high VO2 Max, making them tougher and more fatigue-resistant? To be continued...