Plasma amino acid responses of trained athletes to two successive exhaustion trials with and without interim carbohydrate feeding.

Abstract

The purpose of this research was to measure changes in selected plasma amino acids (AA) during two successive exercise trials to exhaustion. Eleven trained male athletes completed these trials at weeks 4, 6, 8 and 12. Blood samples for each test were collected after a 12-hour fast at times (in minutes) 0 (Resting), 45, 90, 135, 180, at exhaustion (EI), after a 20-minute recovery period, and at the second exhaustion (EII). At the end of EI, subjects consumed an artificially sweetened water replacement (placebo) treatment or a carbohydrate (CHO) replacement (1.1 g CHO/kg BW) in order to determine any effect of CHO replacement on changes in energy substrates or AA, adjusted for plasma volume changes. From baseline to EI, alpha-aminobutyric acid, alanine, glycine, isoleucine, serine, valine threonine, and tyrosine decreased significantly (p less than or equal to 0.05), while taurine increased significantly. During the recovery period following EI, isoleucine, leucine, ornithine, phenylalanine, tyrosine, urea and valine increased significantly. From the end of recovery until EII, alanine, aspartic acid, glycine, isoleucine, leucine, ornithine, phenylalanine, serine, threonine, tyrosine and valine decreased significantly. CHO replacement had no effect on the mean change scores for any AA from EI to the end of the recovery period and affected only serine, citrulline, glycine and threonine from the end of the recovery period to EII.

Changes in plasma and urinary taurine and amino acids in runners immediately and 24 h after a marathon

“…These studies have confirmed some of the earlier studies of changes in a number of amino acids in the plasma after the completion of a marathon (Conlay et al, 1989;Blomstrand and Newshome, 1992;Bazzarre et al, 1992). Such studies have been extended to investigate whether informative changes also occur in the urine, a biological fluid which could be used in preference to the invasive approach of taking blood specimens.…”

Changes in plasma taurine levels after different endurance events

“…During prolonged exercise, depletion of glycogen stores in the muscle occurs, which results in gluconeogenesis using non-essential amino acids as substrates. Alteration in the concentrations of a number of amino acids have been reported after the completion of a Marathon, (Conlay et al, 1989;Blomstrand et al, 1988 and1992;Bazzarre et al, 1992) or a 100km run (Decombaz et al, 1979). Extensive changes in the amino acid pool occurred in both endurance events in this present study, which was associated with the time of endurance of the exercise, a decrease of 25% and 52% respectively.…”

In vitro antioxidant activity and in vivo anti-fatigue effect of loach (Misgurnus anguillicaudatus) peptides prepared by papain digestion

“…Some amino acid, especially the branched chain amino acids, can improve the exercise capability and markedly retard the catabolism of protein in the muscle during exercise (Blomstrand & Newsholme, 1992). Bazzarre, Murdoch, Wu, Herr, and Snider (1992) reported that the amount of amino acids, especially alanine, glycine, valine, isoleucine, threonine, serine and tyrosine in the plasma will decrease rapidly during an endurance test. As shown in Table 1, the loach peptide contains 32.2% of the above amino acids, suggesting that it might enhance exercise capability.…”