Like all great villains, lactic acid has been misunderstood. We’ve been blaming it for the pain we suffer during intense exercise for more than two centuries. There’s nothing worse, we say, than the “lactic burn” that locks our failing muscles into immobility. More recent tellings of the story have tried to rehabilitate lactic acid’s reputation, insisting that it’s actually trying to fuel our muscles rather than shut them down. But that version doesn’t capture the full complexity, either.
Into this confusion steps a new review in the European Journal of Applied Physiology, from veteran physiologists Simeon Cairns and Michael Lindinger. It’s a dense 35-page doorstop titled “Lactic Acidosis: Implications for Human Exercise Performance,” and the clearest conclusion we can draw from it is that the precise causes of muscle fatigue during intense exercise are still a topic of active research and vigorous debate among scientists. But the sudden popularity of baking soda as an acid-buffering performance aid has renewed conversations about how, exactly, lactic acid works in the body—and how…
