The speed at which one’s body transitions from primarily aerobic energy production to increasing reliance on anaerobic pathways is a critical concept in endurance training. It represents the effort level where lactate begins to accumulate in the blood at an exponentially increasing rate, creating a metabolic shift that cannot be sustained for extended durations. For instance, a runner might be able to maintain a certain speed for an hour, but attempting to increase even slightly beyond that speed would result in rapid fatigue and the inability to maintain it for a similar duration.
Training at or near this intensity offers substantial physiological advantages. Consistent training improves the body’s ability to clear lactate, allowing one to maintain higher speeds for longer periods. This type of training has been a cornerstone of endurance athletes’ routines for decades, and is used to increase efficiency at a given workload. This leads to enhanced performance in races and other endurance events.
