The answer is lactic acid/lactate. This is caused by
anaerobic respiration in muscles especially during strenuous physical activity due to low oxygen supply to muscles in respect
to the demand. When there is sufficient oxygen in the muscles, pyruvate is broken down
aerobically in the Kreb’s cycle. However,
it is converted to lactate in the anaerobic
pathway. Lactic-acidosis occurs when
lactic acid accumulates in tissues and slows down metabolic pathways
