Teaching Contemporary Lactate Physiology: Why It Is Time to Retire "Lactic Acid".

The terminology used to teach physiology should reflect contemporary scientific understanding. Although decades of research have fundamentally transformed our understanding of lactate biology, the term lactic acid remains widely used throughout physiology education, textbooks, coaching education, certification programs, and public communication. Under physiological conditions, however, lactate-not lactic acid-is the predominant molecular species, and modern evidence recognizes lactate as an oxidative fuel, signaling molecule, and regulator of metabolism rather than a metabolic waste product. This Perspective argues that physiology education should preferentially adopt terminology consistent with contemporary lactate biology. We discuss the historical origins of the term lactic acid, summarize the scientific advances that have reshaped our understanding of lactate physiology, and propose a practical educational framework for communicating these concepts across diverse learning environments. Aligning educational language with contemporary scientific evidence represents more than a matter of scientific precision; it provides an opportunity to strengthen conceptual understanding while improving the teaching and communication of exercise physiology.