Serum amino acid responses to three different exercise sessions in male power athletes.

Background. The purpose of this study was to investigate serum amino acid responses to 3 different exercise sessions in male power athletes (sprinters and jumpers; n=11). Methods. All subjects performed 2 running exercise sessions: a short run session (SRS) of 3x4x60 m with recoveries of 120 and 360 sec, and a long run session (LRS) of 20 sec runs with recoveries of 100 sec until exhaustion. Ten subjects performed a strength exercise session (SES) of 90 min. Serum amino acids (n=21) were assayed 10 min before and 10 min after the sessions. Peak blood lactate was analyzed from fingertip blood samples taken 1 and 5 min after the sessions. Results. The before-after comparisons showed that the essential amino acids (EAAs) decreased by 8.7% (p<0.01) and alanine increased by 26.7% (p<0.001) after SRS. Following LRS the EAAs decreased also by 8.7% (p<0.01) and alanine increased by 25.3% (p<0.001). In the sum of all amino acids there were no changes after SRS and LRS but a significant decrease (14.8%; p<0.01) was observed after SES. Also the EAAs decreased (20.6%; p<0.001) but alanine, taurine and citrulline were the only single amino acids with no changes after SES. The peak blood lactate concentrations after SRS, LRS and SES were 13.8±1.9, 16.4±1.3 and 2.5±0.4 mmol/L, respectively. The lactate value after SES differed (p<0.001) from the values observed after SRS and LRS. The comparison of the changes in the serum amino acid concentrations following the 3 exercise sessions revealed that SRS and LRS were very similar but SES differed from SRS and LRS strongly (p<0.01) in the sum of all amino acids. Conclusions. The current data indicate that the sum concentrations of all amino acids in serum decrease after the strength exercise session but not after the lactic anaerobic running exercises.