Swings & Roundabouts

[Birchy]

Our body produces lactic acid to "oil" our muscles, but then has a degenerative effect once it has built up....how does this work? Can anybody explain - in lay terms - how and why lactic acid is useful one minute, but harmful the next?

[incitatus]

The answer is in pH buffering effects. Lactate is produced as part of the normal functioning of muscles, and its buffer action assists in muscle use. This action is dependent upon local ion concentrations, though. With insufficient co-ions present, or too much lactate, the pH drops, muscle function is impoverished and some tissue damage can occur.