Surprised you people aren't talking about this

Science, Vol 305, Issue 5687, 1112-1113 , 20 August 2004
Enhanced: Lactic Acid--The Latest Performance-Enhancing Drug

Runners routinely blame their weak and aching muscles on the
accumulation of lactic acid. But not so fast, say Allen and Westerblad
in their Perspective. They discuss a study (Pedersen et al.) revealing
that lactic acid accumulation can, in fact, be beneficial by helping
to restore force to weakened muscles. By altering the activity of
chloride ion channels, lactic acid may actually boost the generation
of action potentials and, hence, muscle activity even as the muscles
begin to fatigue............


Intracellular Acidosis Enhances the Excitability of Working Muscle
Thomas H. Pedersen,1 Ole B. Nielsen,1 Graham D. Lamb,2 D. George
Stephenson2*

Intracellular acidification of skeletal muscles is commonly thought to
contribute to muscle fatigue. However, intracellular acidosis also
acts to preserve muscle excitability when muscles become depolarized,
which occurs with working muscles. Here, we show that this process may
be mediated by decreased chloride permeability, which enables action
potentials to still be propagated along the internal network of
tubules in a muscle fiber (the T system) despite muscle
depolarization. These results implicate chloride ion channels in
muscle function and emphasize that intracellular acidosis of muscle
has protective effects during muscle fatigue.

"Lame Acer" wrote
Science, Vol 305, Issue 5687, 1112-1113 , 20 August 2004
Enhanced: Lactic Acid--The Latest Performance-Enhancing Drug

Yeah, I heard that on Morning Edition today:
http://www.npr.org/features/feature.php?wfId=3861103

-Brendon