Originally Posted by Brian Stone
That's interesting. I only read your highlights so far. I seem to remember reading an article or sniplet recently on this subject that suggested there were fibers that were neither fast nor slow twitch but that had the potential to be either one based on training. I'm unsure of the validity of that, or how elastic their potential is after differentiation (assuming that this occurs at all).
You're probably referring to hybrid muscle fibers. The first article I posted seemed to indicate that the elderly tend to have more hybrid muscle fibers and not more slow fibers as we had once assumed. I wonder if any research in the past 8-9 years has validated or disproved this.