What role does lactic acid play in exercise?

Lactic acid is a byproduct of anaerobic metabolism, which occurs when the body breaks down glucose for energy in the absence of sufficient oxygen during intense exercise. This accumulation of lactic acid in the muscles is associated with muscle fatigue, as it can lead to changes in pH levels within muscle cells. When lactic acid levels rise, this shift in acidity can inhibit certain enzymatic reactions required for muscle contraction and energy production, resulting in the sensation of fatigue and a temporary decrease in performance.

This helps explain why during high-intensity activities, as lactic acid builds up, individuals may experience a burning sensation in their muscles, which is often linked to this discomfort and fatigue. Understanding the role of lactic acid is crucial for fitness instructors, as it allows them to educate clients on exercise physiology and the effects of different energy systems used during workouts.