On p. 413, the text “Furthermore, accumulation … metabolism (Westerblad et al. 2002).” should read “Furthermore, the increased release of H+ ions during intensive exercise (mainly due to increased ATP hydrolysis?) that is accompanied by increased lactate levels (“lactacidosis”), could be co-responsible for limiting physical performance (Gladden 2004). It has been considered that “lactacidosis” could contribute to the induction of fatigue by several mechanisms (Gladden 2004; Westerblad et al. 2002).” On p. 418, the sentence “It seems that … in the plasma.” should read “It seems that an outflow of lactate from erythrocytes is possible, despite the fact that lactate levels are higher in plasma.”.