Eight part
Few words on languages and lactate.
When I met Rolando Hinojosa it was a real pleasure. He was joking with me in Spanish, attentive, bright and funny. Wikipedia: Rolando Hinojosa (born 1929) is a novelist, essayist, poet and the Ellen Clayton Garwood professor in the English Department at the University of Texas at Austin. Rolando was asked to present his work at the University of Appleton in Wisconsin; I was there to listen to the writers; and for an obscure reason he sat next to me. He is more than a fully bilingual guy. He has control of the emphasis of the language as nobody. He is another person in English. Then, he was the Chairman of the Department of English at the University of Texas at Austin. Rolando was not joking anymore as a Mexican clown when presenting his work. He was “the man” and did not exist as such in Spanish. He was behaving in English. I spoke about him to my supervisor and father-like-figure, Richard Phillips, MD, a psychiatrist who was a poet, Professor Emeritus at SUNY Syracuse. He told me bluntly, “If one is the Chairman, one speaks English and has no doubts.” Once more, “language can deceive us.”
When speaking about lactate, I have to show you a different way of looking at it. Another language so we can see something else helpful; like Hinojosa when speaking English. In Medicine there are many monuments left for our heroes and at the end it is difficult to see “the real.” Lactate is the most effective transport of energy for our body in the “fight or flight” situation; when the body has an emergency, lactate is produced. OUR BRAIN NEURONS USE LACTATE AS THE ONLY FUEL to do our daily task. I assume that neurons use it in general as the main fuel. So, lactate is “good.” We have to produce lactate to get the neuro-fibers firing. Around 4millimols per cc of blood allows us to finish an Olympic Distance Triathlon at our best pace. The more tolerance we acquired to lactate the better we are. Here, it is important to point out that sometimes the cybernetic equilibrium is lost and lactate continues to increase without being used by neurons or other cells (not in the case of Lance Armstrong as you will see below). Anecdotally, we can say that even if we finish a marathon in “the sweet spot,” our lactate goes up above 10. It means, we have a tolerance to lactate above 4. Dr. Cheung in his article writes regarding the subject.
An individual’s Lactate Threshold is the single most important physiological determinant of endurance exercise performance. It is trainable, reliable, and a sort of proxy for other important metabolic processes that underlie performance.
Another example regarding lactate and performance we have it with Armstrong. He was unable to have high lactate levels in blood, no because he did not produce it; but, I venture to say that he was able to utilize lactate efficiently due to his high cadence. His neurons use it right away to keep firing at a high cadence.
J Appl Physiol 98:2191-2196, 2005. First published 17 March 2005;
Improved muscular efficiency displayed as Tour de France champion matures
Eight months after chemotherapy for cancer and during a period of inconsistent and reduced training (i.e., August 1997), VO2 max was 5.29 l/min and 66.6 ml/kg/min. Furthermore, at this time of reduced training, maximal blood lactate concentration measured 4 min after exhaustion was 9.2 mM compared with previously recorded values in the range of 6.3–7.5 mM. Maximal heart rate declined from 207 to 200 beats/min from 1992 through 1999. The VO2 corresponding to the blood lactate threshold was 4.5– 4.7 l/min when measured in 1992–1993 and, as expected, it was reduced to 4.02 l/min during the period of reduced training in August 1997.
As cycling efficiency increases due to increased percentage of type I muscle fibers, it is possible that increased power is manifested by increasing cycling cadence (i.e., velocity) rather than increasing the muscle forces directed to the pedals. This approach appears to produce less sensation of effort relative to muscular strength (27). Therefore, it is likely that the increases in freely chosen cycling cadence displayed over the years by this Tour de France champion reflect his increased mechanical efficiency, agreeing with the pattern expected to result from muscle fiber conversion from type II to type I.
Well, I hope you have a better understanding about lactate applying a cybernetic model. I will speak about Gregory Bateson and what children should know in the future.
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