Due to accumulation of which acid in the muscles, man feels tired?

Due to the accumulation of (a) Lactic acid in the muscles, a person feels tired. During intense physical activity, the body’s demand for energy increases. When oxygen supply to the muscles cannot keep pace with this demand, such as during vigorous exercise, the muscles switch to anaerobic metabolism.

During anaerobic metabolism, glucose is broken down into pyruvate, which is then converted into lactic acid when oxygen levels are low. The buildup of lactic acid in the muscles leads to a drop in pH, resulting in muscle fatigue, soreness, and a sensation of tiredness.

Although lactic acid was previously thought to cause muscle fatigue, recent research suggests that it may actually play a role in providing energy to muscles during strenuous activity. However, its accumulation can still contribute to the sensation of fatigue experienced during prolonged or intense exercise, making it a key factor in understanding muscle fatigue and performance.