VO₂ Testing

Most fitness testing involves tools and methods taken from other, more-proper disciplines. For instance, the Beckman cart was originally intended to measure VO₂Min (minimum volume of oxygen) to assess basal metabolism in comatose patients. It was not intended as a performance test as VO₂Max (maximum volume of oxygen). (Note that performance is nil with a comatose patient.) Regarding this, please refer to The Nautilus Book by Ellington Darden, PhD. Therein are sections where Keith Johnson, MD, criticizes VO₂Max testing as inappropriate. I met with Dr. Johnson in the summer of 1992 and asked him if he had changed his views regarding such testing. He emphasized that The Nautilus Book references were accurate and current.

For VO₂Max testing to be seriously attempted, a seal must be maintained between the air exchange of the subject and the Beckman Cart. There exists an unavoidable error of calibration for the gases in the hoses between subject and Beckman Cart. To keep this error at a minimum and constant, only steady state activity is reasonably tested. This permits use of short hoses to minimize the volume (dead space) of the gases between the subject and the Beckman Cart.

For instance, if a full Nautilus circuit is to be used, the hoses and cart would be required to follow the subject along the circuit. In addition to this inconvenience, the hoses might preclude several key Nautilus exercises due to hose interference. And if such interference could be avoided, special consideration to redirect the hoses or change their orientation with each exercise would greatly compromise the exercise intensity. This explains why exercise physiologists are typically adamant regarding the need for steady state activity to serve as exercise. It is the only activity that lends itself to be tested by their test.

Note the picture above. As oxygen consumption is measured, a horse is running on a treadmill as is assumably required if measuring equipment is applied to a horse. Either the equipment must go with the horse or the horse must be tethered to the equipment. Either way, steady state activity remains imperative for testing. Consider the fact that it is not possible to teach a horse or another animal subject to perform movements according to muscle/joint function. It must be tested in its typical mode of locomotion. It becomes only natural that exercise physiologists become trapped in a mindset of locomotive behavior for testing purposes.

The use of treadmills originated with the use of draft animals — including humans — for the purpose of supplying power to drive industrial machinery. I do not know if oxygen consumption measurement originated with the application to other animals or if it was first used on humans, then applied to horses and other animals. The general practice of such measurement seems to have been around since the 1920s. Its use was the result of earlier work by in 1907. These origins are detailed somewhat by D. J Sharkey in New Dimensions in Aerobic Fitness. [Note that the title of Sharkey's book uses the proper biochemical adjective aerobic without an s to imply the legitimacy and emphasis of the aerobic metabolic pathway as the only exercise importance, although the exercise physiology stance actually resides in the pop culture perversion of aerobics - Ken Cooper's slang that includes the s. I attempt to apply these variations consistently in my writings.]

With human subjects, another approach might be to avoid hoses altogether by placing the subject and several exercise machines in an airtight bubble. Although this would facilitate the freedom of movement for more ideal exercise, the dead space error would be enormous and unmanageable.

We further assume that the testing equipment is properly cleaned and calibrated. Dr. Johnson originally doubted the precision of the uptake testing equipment until he found that proper calibration rendered a reliable tool. However, he hedges that most physiologists do not adequately maintain their equipment or appreciate the need to do so.

Ellington Darden states that accurately testing oxygen consumption in any activity other than treadmills or something akin to stationary bicycles is like "trying to type while riding a stage coach."

Assuming an accurate test is possible, attempts to make something of VO₂Max testing are unsuccessful. According to Darden, no one has found a disease or condition that VO₂Max detects, qualifies, or quantifies. According to Darden, VO₂Max is a test looking for a problem to measure.

On January 13, 1995, Michael Pollock, PhD, admitted to Ellington Darden that VO₂Max testing is no test of anything and almost totally a genetically dependent variable. This is outrageous since Pollock, more than Kenneth Cooper or any other one person, has done more work in this country to set up exercise physiology degree programs, certification programs with the American College of Sports Medicine, and cardiac rehabilitation programs with VO₂Max testing as its basis. This has resulted in the present $3 billion fitness industry.

VO₂Max is now documented to be almost completely genetic and can vary only slightly due to training effect (exactly what Keith Johnson asserted). A Klissouras, V. was the first name on “Heredibility of Adaptive Variation” in the Journal of Applied Physiology (Vol.31, No. 3 pp. 338-344, 1971) as well as “Genetic Limits of Functional Adaptability” in Int. Z Angew Physiology (Vol. 30, pp. 85-94, 1972). In these papers, and over 20 years ago, Klissouras documented that VO₂Max is 93.4% genetically determined in males and 95.9% genetically determined in males and females together. The fact that we can expect only a 4-6% improvement due to environmental control strongly suggests that VO₂Max, if a reliable test, is not an appropriate test to study human health.

Other authorities condemn the futility of VO₂Max testing. Ted Lambrinedes, PhD and George Sheehan, MD (cardiologist) have made bountiful arguments against it.

Brian J. Sharkey, PhD, (New Dimensions in Aerobic Fitness, © 1991) elaborates many of the inconsistencies of VO₂Max testing, but then hedges his conclusions as if to stretch a rationalization for its practice. He admits that his attitude toward VO₂Max has gone from extreme belief in the test to confused disappointment since the beginning of his 30-year career. His arguments seem to be organized along a line of cardiovascular fitness: staying well clear of using it to denote health. Sharkey also makes a plea for tests that are more specific to the activity performed. Here is a case of an exercise physiologist who seems to approach the subject reasonably, but fails to apply the principles of motor learning, the six factors of functional ability, the Exercise vs Recreation argument, or The First Definition of Exercise.

A more extreme stretch is made when - in the absence of a Beckman Cart - VO₂Max is measured indirectly with a bicycle ergometer based on a protocol that correlates performance (metabolic work units termed metabolic equivalents => Mets) on the bicycle to oxygen consumed (Mets) with a known VO₂Max calibration. Since metabolic work can not be measured - a la Arthur - this is horribly sloppy, although widely accepted and taught in exercise physiology and certification courses. (Note that the word ergometry implies that metabolic work can be measured.)

In The Exercise Myth (© 1984) cardiologist Henry Solomon states that Columbia University cardiologist Jonathan Moldover "denies there is such a thing as cardiovascular fitness, because fitness is related to peripheral changes." Corollary to this testing issue, Solomon states that there is no correlation between cardiovascular fitness and cardiovascular health. He also notes that the presumed development of protective collateral coronary arterial supply due to exercise is just as likely due to the stimulus of a survived heart attack.

In the 1970s Arthur Jones admitted that he knew little or nothing about the validity of VO₂ testing equipment. He then qualified his admission further with statements to the effect, "but I am aware of the gross inaccuracies of the tools used to measure strength. And since the same kind of fools who developed the strength testing equipment also were the same kind of fools that developed VO₂ testing, what can I safely assume?