The lactic acid diffuses out of the muscles and is taken to the liver by the blood. The liver can change lactic acid back into glucose: however, this conversion also requires the use of ATP. During strenuous exercise, primarily the muscles and not the liver use the oxygen, so the lactic acid accumulates.
/quenchÂ·ing/ (kwenchÂ´ing) 1. suppressing or diminishing a physical property, as of heat in a metal by immersion in cold liquid. 2. decrease of fluorescence from an excited molecule by other molecules that absorb some emission energy that would otherwise occur as light.
Taking steel as example, it is quenched in water. It may be quenched few rounds in heat treatment. If slower cooling required it may be air cooled or cooled in furnace. Quenching in oil is rare. Quenching is only perform on metal that requires certain characteristics, common metal you use everyday is not quenched.