I once was asked to write a foreword to an interesting book about a group of endurance athletes. In doing my research, I learned something quite remarkable. But before I tell you what that was, I need to provide some background on one of the true marks of a good endurance athlete.
VO2 max is a measurement of the maximum amount of oxygen an individual can utilize during intense physical exertion. This capacity is generally considered the best indicator of cardiovascular fitness because the greater volume of oxygen that can be used during high-level exercise, the more energy (ATP) that can be produced, leading to better performance. VO2 max is therefore a gold-standard of fitness and aerobic endurance.
Some athletes have recorded amazingly high VO2 max levels. Cycling legend Greg LeMond had a VO2 max of 92.5 milliliters of oxygen per kilogram of body weight per minute. Matt Carpenter, the Pikes Peak Marathon course record holder, recorded a 92.
In other endurance sports, Olympic cross-country skiers have scored even higher, though no one has ever cracked 100. Personally, I’ve only reached the upper 70s when tested.
But this led me to ponder, how would a human stack up against an animal, such as a cheetah or a thoroughbred racehorse? (We did just have the Kentucky Derby.)
Turns out, not very well.
Racehorses have an extremely high VO2 max of 180, primarily because their hearts are as big as basketballs and can pump huge amounts of oxygen-rich blood throughout their system. Cheetahs, on the other hand, are sprinters designed for short bursts, so their VO2 max levels are lower than elite human endurance athletes.
More From Runner's World
So just who is it that rules the world when it comes to stamina? You might actually have one in your household. Dogs have tremendously high VO2 max scores. In fact, the Iditarod Trail Race sled dogs may be the fittest animal athletes on the planet, some recording VO2 max levels over 200!
How do I know this? Because the book I wrote the foreword to is called Born to Run: Athletes of the Iditarod.
Here’s the takeaway: Many coaches advise that if you want to improve, train with someone who’s faster than you. So leash up your favorite speedy Fido, and hit the road!