Elite athletes have gut bacteria that eat muscle waste
While most people struggle with the burning sensation of lactic acid, top-tier marathoners host microscopic passengers that transform that painful waste into a high-octane energy source.
The burning sensation in your legs during a sprint is caused by the buildup of lactate, a metabolic byproduct that usually signals the body to slow down. However, researchers analyzing the stool of runners from the 2015 Boston Marathon discovered a specific genus of bacteria called Veillonella that thrives on this exact waste product. These microbes act like a secondary engine, blooming in the gut immediately after a race to gobble up lactate and convert it into propionate, a short-chain fatty acid that the body can cycle back into the bloodstream as fresh fuel.