Re: muscle twitch types..question

Tivers@aol.com
Fri, 22 Nov 1996 13:38:00 -0500

In a message dated 96-11-22 10:51:04 EST, you write:

<< thanks for the great conversations of late...

What are fast muscle twitch types (I guess compared to slow?) In
layman's terms please. :)

Kimberly (&Mystery the Morab)
Petaluma, Ca
>>

The horse has an ample supply of three generalized fiber types (many fibers
in-between, changing one way or another). The Slow Twitch (ST or Type 1) are
slow-contracting muscle fibers that have high oxidative capacity--can burn
fuel right down to CO2 and water. Fast Twitch (FT or Type 2b) are
fast-contracting muscle cells with very little oxidative capacity--they burn
fuel without oxygen and leave "smoke" behind, in the form of lactic acid.
Fast Twitch High Oxidative (FTH or Type 2a) share characteristics of FT and
ST cells--they contract more quickly than ST, but have oxidative capacity--we
want a lot of these cells in racehorses.

ti