INTRODUCTION: Exercise is accompanied by increased protein catabolism and changes in the plasma amino acid concentrations, as amino acids both influence on and reflect muscle protein synthesis and breakdown (van Loon 2014). For example, branched-chain amino acids leucine, isoleucine and valine affect protein synthesis in human skeletal muscles (Blomstrand et al. 2006) and ultra-endurance exercise causes muscle protein breakdown elevating plasma phenylalanine and tyrosine concentration (Borgenvik et al. 2012). In addition prolonged exercise and overtraining may decrease plasma glutamine concentration (Parry-Billings et al.1992). METHOD: Four young males (18.5 ± 1.05 years) and four young females (17.9 ± 0.86 years) participated in the study, all of them cross-country skiers from the Vuokatti-Ruka Sports Academy. During their training and competition season (Aug. 2014 - Mar. 2015) plasma amino acid profiles of the study subjects were determined eight times. The plasma samples were deproteinized (Borgenvik et al. 2012) and free amino acids were analysed by HPLC (Agilent 1100) connected to a fluorescence detector using commercially available Waters AccQ?Tag Amino Acid Analysis Method with modifications. RESULTS: A total of 12 amino acids were identified from plasma. A typical amino acid profile in a plasma sample is represented in Fig. 1. The amino acid profiles of the athletes were compared with routine clinical laboratory analyses conducted to them and with their training load. In the presentation, we will show the most typical and interesting changes in the amino acid profiles of the study subjects. DISCUSSION: There is ongoing debate on the necessity of protein and amino acid supplements for athletes training strenuously. Research on the subject is especially important when the nutrition of young and developing athletes is considered. This study provides valuable data on amino acid profiles of a small group of young cross-country skiers over a relatively long period when their physical stress and training load varied significantly. --- The hosting University of Jyväskylä is planning to publish conference proceedings "Science and Nordic Skiing III". In case you are interested in this publication please contact the editors (Anni Hakkarainen anni.s.j.hakkarainen@jyu.fi) to become registered for the book.
© Copyright 2015 3rd International Congress on Science and Nordic Skiing - ICSNS 2015. 5-8 June 2015, Vuokatti, Finland. Veröffentlicht von University of Jyväskylä; University of Salzburg. Alle Rechte vorbehalten. / Übersetzt mit https://www.DeepL.com/Translator