In the world of endurance, it seems that you cannot discuss fitness without discussing VO₂ max.  Ask any endurance athlete about it and you will hear epic stories with names like Indurain, LeMond, and Armstrong.  Many of you however, may find yourselves wondering what exactly VO₂ max is and why is it so important.  To better understand this concept let’s take a little trip back to school, specifically back to physiology class.  According to the Essentials of Strength Training and Conditioning textbook, VO₂ max is the maximum amount of oxygen in milliliters, one can use in one minute per kilogram of body weight (ml/kg/min).  In other words, maximal oxygen uptake (VO₂ max) is the greatest amount of oxygen that can be used at the cellular level for the entire body.  VO₂ max has been found to correlate well with an individual’s degree of physical conditioning, and has been accepted as an index of total body fitness.  Numerous studies show that one can increase his/her VO₂ max by working out at an intensity that raises the heart rate to between 65 and 85% of its maximum, for at least 20 minutes, three to five times per week. The estimated mean value of VO₂ max for male athletes is about 3.5 liters/minute, and for female athletes is about 2.7 liters/minute.

Now that we know what VO₂ is, we can now answer the question, “Why is it so important?”  For the endurance athlete, VO₂ has long been considered the holy grail of fitness.  The common rationale is the better one can utilize oxygen, the higher the level one can perform in endurance events.  Is this however, really the case? 

Although VO₂ max is an important component of any endurance program, I have both good news and bad news for those of us who have may not have chosen the right parents!  The bad news is that according to Exercise Physiologist Neal Henderson, Coordinator of Sport Science at the Boulder Center for Sports Medicine in Colorado, VO₂ is approximately 80% genetic.  Other estimates put this number anywhere between 30-60%.  Whatever the number is, one thing is certain; there is a genetic ceiling for VO₂.  The good news is that VO₂ is trainable.  Unfortunately, if Neal Henderson’s 80% estimate is correct, and your VO₂ is, for example, at 45ml/kg^-/min (average), your best may only be 52 ml/kg^-/min after a 20% gain (52 ml/kg^-/min is considered to be good or just above average).

To put this into perspective, Lance Armstrong checks in at about 84ml/kg^-/min, while cross-country skier Bjorn Daehlie measured at an astounding 96 ml/kg/min.  The highest VO₂ max ever recorded in a lab was 300 ml/kg/min!  This, of course, did not belong to a human, but rather a pronghorn antelope.  How they got the antelope to run on the treadmill I’ll never know, but I promise I’m not making this up.  Thoroughbred horses have a VO₂max of around 180 ml/kg/min, and Siberian dogs running in the Iditarod Trail Sled Dog Race sled race have VO₂ values as high as 240 ml/kg/min.  To add even more perspective, Olympic marathon winners and elite runners like Jeff Galloway, Alberto Salazar and Frank Shorter check in among the low to mid 70’s (see Table 2 for a list of athletes and their respective VO₂’s). 

The good news is, like the previously mentioned runners, although you may be at your genetic potential, there are many factors besides VO₂ max that can also influence your success in endurance performance.  Improving efficiency and economy of movement as well as raising your anaerobic threshold (LT) can lead to performance enhancements in the absence of increases in VO₂.  These three components can all be addressed through a functional strength-training program.  Now let’s take a closer look at each of these components.

  Continuing on, in our physiology lesson, now would be a good time to talk about lactate threshold (LT) and its relationship to VO₂.  Dr. Stephen Seiler of Masters Athlete Physiology and Performance says, “For the endurance athlete, a high VO₂ max is like having an invitation to the big dance but having an invitation to the dance does not ensure you will dance with the prettiest girl.”  If you want to dance with that girl, you are going to have to work on your LT! (And you thought it was big guns and washboard abs that attracted the girls)  LT, as pointed out in one of my previous articles (see Lactic Acid; The Good, The Bad, and The Ugly), is the point where the body produces more lactic acid than it can clear.  Training LT will result in a decrease in lactate production at any given exercise intensity.  Untrained individuals usually reach the LT at about 60% of VO₂ max. This means that even if my VO₂ is 70 ml/kg/min, which is an elite level, I can only use 60% of it, or 42 ml/kg/min (average), before my LT shuts me down.  With training, however, LT can increase from 60% to above 70% or even higher. Elite endurance athletes typically have an LT at or above 80% of VO₂ max.  Although most endurance athletes usually train LT in the pool, on the bike or during the run, we have several protocols in the gym designed specifically to improve LT.  Furthermore, because specificity of movement is very important when training LT, these protocols address both the lower and upper body (See table 1).

    Last but not least, we can now tackle efficiency and economy of movement.  The difference between efficiency and economy in an exercise setting is that, for a given energy consumption, economy is measured as movement velocity, while efficiency is measured as mechanical power output.  What does all that mean?  It means that efficiency and economy can be just as important as VO₂ or LT.  To better understand this concept just think of the last time you were out for a group ride.  Was it easier to pull at the front or sit in?  Sit in, of course!  Why is that?  Because sitting in allows for more efficient movement and less exertion, which in turn will allow you to be more economical.  Think of every joint in a given movement as an opportunity to leak power.  The more joints involved in a movement, the more opportunity there is to leak power;  the more stable the joint, the less power that leaks; the less power that leaks, the more efficiency in a given activity. 

So how do these concepts apply to strength training? Frequently, I am asked to watch someone run on the treadmill and look at their gait.  Instead, I ask them to perform 10 anterior reaches (see exercise of the month-Jan.) on a single leg.  If this is difficult, that tells me their hips are not as stable as they could be and their gait could not possibly be as good as it should be.  The same goes for the shoulder joint.  If you cannot manage a set of t-stabilization push-ups (again, see exercise of the month-Feb.) with good form, then your swim stroke is not as efficient and economical as it could be.

Now for all of you skeptics out there, all I ask is for you to just try it.  Perhaps before the next time you go to test your VO₂ (no fun by any means), you might first try taking a look at your anterior reaches or t-stab push-ups or the protocol listed in Table 1.  These alternatives are not meant to point out your shortcomings or embarrass, but rather to empower you.  Rather than whining about genetics (though, trust me, I still do), try testing your limits in some of the ways mentioned earlier.  I assure you that you will find what my most successful clients have found; that through a comprehensive functional strength-training program, economy, efficiency and lactate threshold can be improved, making maximal VO₂ less important.

Table 1

Super Legs

Complete entire circuit without resting in less than 1:30  

Table 2

VO₂    Athlete    Sport