The effect of preceding anaerobic exercise on aerobic and anaerobic work

The effects of exercise-induced elevation of lactic acid concentration in blood [Lab] up to 12-14 mM on the subsequent aerobic (less than or equal to VO2 max) and anaerobic (supramaximal) performance was investigated in a group of trained non-athletic subjects. For submaximal loads ranging from 0.6 VO2 max to VO2 max the VO2 max/external work load (Wext) ratio was unaffected by preceding anaerobic exercise, VO2 max was not significantly different, whereas the maximal performance time of a standard exercise was reduced. The kinetics of the VO2 on- adjustment at the onset of 0.9 VO2 max rectangular loads carried out by the arms and/or by the legs was significantly increased by a preceding supramaximal anaerobic load carried out by the same as well as by the non-exercised limbs. It is concluded that in the presence of high [Lab] (1) the maximal aerobic power (VO2 max) is unchanged; (2) the efficiency of aerobic work is unaffected, which implies that during active recovery most La is used as substrate, provided the metabolic level during the latter exceeds 0.6 VO2 max; (3) the endurance for anaerobic as well as for aerobic exercise is reduced; (4) the kinetics of the VO2 adjustment at the onset of submaximal rectangular loads is faster, both in primed and in non-exercised muscles.