The accumulation of lactate in the muscle tissues after strenuous exercise
induces a phenomenon of fatigue with a lowering of performance capability. The endeavor
to overcome the fatigue via supplying high energy sources faces the contradictory
reality that such a strategy might cause a higher accumulation of lactate in the tissues.
As for the fate of lactate in the anerobic state of exercising muscle tissues, the transamination
of pyruvate to alanine would eventually lower the content of lactate in addition
to the well-known Cori cycle (Park et al., 1989). Moreover, since the enzymes of GPT
and LDH are of near-equilibrium properties, the reactions are mostly dependent on
the concentration of substrates. Therefore, in the present experiment, we tried to determine
the effect of amino acid administration, especially of glutamate, on the exercise
performance in long-distance runners and high school cyclists to see whether the lactate
level could be lowered. The results can be summarized as follows: (1) the lactate clearance
in the blood was accelerated in the glutamate-administered group; (2) the blood
level of lactate during strenuous exercise was lowered in the glutamate-treated group;
(3) the performance of exercise was improved partially in the glutamate-treated group.
From these results, it can be suggested that glutamate administration before exercise
might reduce lactate accumulation, leading to improvement of exercise performance