Originally Posted by berny
As I understand it (with my mega history of cycle racing stuff), lactic acid is a wonderful source of energy but not easily accessable. Seems like I read somewhere you gotta be in dire straights before the body starts to convert it........ or something like that.
Lactic acid is indeed an energy source: "
The lactic acid system is capable of releasing energy to resynthesise ATP without the involvement of oxygen and is called anaerobic glycolysis.". But it doesn't cause the burn. That is caused by excess hydrogen ions (produced during the breakdown of carbs within the cells) creating an acidic environment that irritates open nerve endings within the muscle mass. Ain't cellular biology excitin'!
And no, you don't have to be in dire straights to use lactic acid. Production & removal of lactic acid continues at rates of 300-500% of resting rates while oxygen consumption has stabilised at
submaximal levels to satisfy the additional energy requirements of heart, lungs, and working muscles.
http://www.cytosport.com/science/lacticacid.html
http://www.brianmac.demon.co.uk/lactic.htm