Participation of blood cells in the changes of blood amino acid concentrations during maximal exercise

We determined the participation of the cellular compartment in the changes of plasma amino acid concentrations during maximal exercise test on a cycle ergometer. Following an overnight fast, male athletes were submitted to a maximal exercise test until fatigue (for 25 min approximately) to determine maximal oxygen uptake. The amino acid concentrations in total blood, plasm a, and blood cells were determined before and after the maximal exercise te st. Most essential amino acids were decreased significantly in the total bl ood concentration as a result of the maximal exercise test. However, the co ncentrations of most nonessential amino acids tended to be significantly in creased. Amino acid concentration was increased most in plasma. Concentrati ons of blood cell alanine and proline were significantly increased by 26% a nd 15%, respectively, after the maximal exercise test. No significant diffe rences in blood cell concentrations of other amino acids induced by the exe rcise rest were found, although the amount of tryptophan in blood cells was increased after exhaustive exercise. (J. Nutr. Biochem. 11:81-86, 2000) (C ) Elsevier Science Inc. 2000. All rights reserved.