"In this past month's issue of Velo News they had a section, 'Fact or Fiction,' where they demystified several myths. One was particulary interesting that concerns lactic acid and it's role in muscle fatigue/burn. Here's what they said: ""Lactate or 'lactic acid' does not cause fatigue nor acidosis. Lactate production actually reduces the rate of acidosis during fatiguing workouts and is an important fuel for exercising muscles, nervous system, and heart. What are we measuring in a lactate threshold test? Ironically, we're measuring the appearance in the blood of a fatigue-limiting substance, rather than the cause of fatigue. The truth is, lactate is our friend and not the villainous 'acid' it was once thought. I thought this was very intersting and wanted to share. The other good myth had to do with anaerobic threshold, that's a lot of hot-air too. we are always using out aerobic system in a sport like cycling."
lactic acid myth
I have been searching my book shelves to remember where I first read this.
This is like the low-fat and the low-carb diets. Eventually science has proved science wrong.
If this is true, does this mean that Lance has been training incorrectly for all these years?
What week of last months Velo news was this in?
"""How was Lance training all these years""? He is on the leading edge of this and its probably not what you think."
"""...lactate is our friend and not the villainous 'acid' it was once thought...""
Hmmm, really, John?!? Have you been experimenting much? Perhaps members of the female audience will agree with you. ;-)"
..are we asking if John has been breast fed?
Lactic acid is a byproduct of anaerobic metabolism of glucose. It dissociates into lactate and hydrogen ion. The lactate can be used as an energy source by many of the body's cells.
The hydrogen ions in the blood are the cause of acidosis, whether from the breakdown of lactic acid or other processes. The hydrogen ions are buffered by other chemicals in the bloodstream.
I have been doing a good deal of reading on this subject. Based upon that, I would interpret the article in VeloNews to be telling us that lactate is not a villain, but it is of no help in the blood stream, either.
Various types of training help us to increase the buffering capacity of our blood (reducing acidosis) and to transport lactate from the blood to cells that need it (thereby keeping us below lactate threshold). Working at higher than lactate threshold shows that our muscles are not using lactate efficiently. What I would like to learn from further reading or from this message board is: Does the anaerobic system, when its products are properly buffered and absorbed, kick in to supplement the underlying aerobic system?
Cycling is a predominantly aerobic activity, but there are times when our muscles get some of their energy from the anaerobic metabolism of glucose, as well as from the breakdown of Creatine phosphate, whose phosphate then combines with ADP to form ATP.
Try googling George Brooks and Lactate Shuttle for further thoughts and theories on this. Jan Olbrecht and lactate.com are other sources along these same lines.
