Posted by: tom.guerry (tom.guerry@kp.org) on Wed Jan 4 22:18:15 2006

Jim-

This is an area where I think the Nyman setpro info is excellent.

Medical evidence for changing inborn proportion of muscle that is fast twitch is not too
convincing,however, with overload/underload training with "augmented feedback"
(batspeed/timing) and intent to hit hard, short term (matter of weeks) improvement can
be achieved via so-called "neural recruitment" which is a way of getting as many of the
existing fast twitch fibers to fire together on demand.

Much longer term training can strengthen/hypertrophy fibers and also lead to gains. See
old setpro site for info.