Disadvantages of Lactic Acid in Human Performance

Lactate is produced as a result of ATP formation via non oxidative energy system – glycolysis

Increased lactate concentrations in the blood have been observed, resulted in decreased athletic performance

Increase abundance of H+ ions can change the pH level.

Negative effects of lactic acid could be multi-factorial

Increased levels of lactate and H+ ions could impair SR Ca 2+ release channels

H+ could depress Ca 2+ activation of actin myofilaments

H+ induces a reduction of the Ca 2+ reloading into the SR

Additional controversies: Difficulty in extrapolating the results to in vivo

conditions – exercise performance in humans

Studies based on isolated, non contracting muscle and skinned muscle fibers resulting in artificial non exercise related conditions

Positive correlation between transport capacity and performance, suggesting that lactic acid accumulation is a disadvantage.

Although high levels of lactic acid & low pH are not primary cause of fatigue, it appears to contribute to fatigue during intense exercise