Originally Posted by Donald Lee
I don't get what you're saying, Mike. I mean, I don't get how you're trying to argue against what Joel over at www.8weeksout.com
was saying. How does what you're saying relate to the central vs. peripheral adaptation contributions for endurance events?
OK...I think I get it now. Is this what Joel said?
There has been a debate for years in exercise physiology about whether the limiting factor in aerobic performance comes from the cardiovascular supply side or oxygen utilization within the muscles themselves. There are arguments for both sides within the literature and I don't think there is really a clear answer yet but regardless, performance depends on both supply and utilization as well as contractile properties of the muscles, technique and skill, etc. It's probably a bit simplistic to say there is any one piece of the physiological puzzle that is single most important. When it comes to performance, it's all important.
If he is talking about VO2 max, he is dead wrong. There is only really one guy arguing that the cardiovascular system is not the limiter for VO2 max. His name is Dr. Tim Noakes. There are not "arguments for both sides" that are credible. The preponderance of the research data is clear and has been for 20 years. The limiter for VO2 max is the ability to deliver oxygen rich blood to the muscles. Anybody who believes otherwise is either ignorant of the research literature on the subject, or their name is Dr. Tim Noakes. I am not necessarily bashing Dr. Noakes. He is a very smart man who has done a ton of great work on fluid balance and exercise, but on this issue he is wrong.
All of this pertains to VO2 max, an exercise intensity that elicits the max utilization of oxygen. At intensities below this level, performance is determined by metabolic capacity of the recruited muscles, not oxygen rich blood delivery.....even for something like a 3K, but even more so as the distances get longer. If what Joel meant by "aerobic performance" was not VO2 max, then I would say that he is wrong anyway, because we know what causes fatigue and what determines performance at intensities at, above and below VO2 max. It is not a mystery.
Doesn't matter. It is all physiology mumbo jumbo for the most part. Just train right and all will be good.