Have you ever thought about what it is exactly that drives improvement in aerobic work capacity? If you are like most people you probably haven’t really felt compelled to ponder this. Even though I am trained pretty extensively in cardiovascular physiology and training theory, I am an anaerobe and a musclehead. What makes muscle work, become stronger, bigger, or more powerful is my interest.
That means that I hadn't, until recently, considered the question either. In fact, if I had been asked that question two years ago, I probably would have pulled an answer out of some old aerobic dogma buried in my brain somewhere, obtained from reading texts and research journals or from sitting in a lecture hall somewhere. I accepted fairly unquestioningly (albeit with a few exceptions in programming issues) the conventional wisdom of aerobic training physiology. I was a happy camper. I didn’t know I actually cared about a higher level of understanding pertaining to aerobic fitness.