INTRODUCTION: Oxidative stress is characterized by an imbalance between antioxidants and oxidizing species of the body. Increased production of free radicals overwhelms antioxidant defenses resulting in cellular damage and oxidation of biomolecules (Wood et al. 2006). In athletes, prolonged exercise and physical stress lead to increased levels of oxidative stress indicators in blood. It may be seen as reduced performance, tissue damage and even overtraining syndrome if recovery periods are not sufficient (Finaud et al. 2006). Oxidative stress can be quantified by measuring metabolites formed by oxidation. Several metabolites have been introduced in the literature, such as the carbonyl groups, isoprostanes and 8- hydroxydeoxyguanosine (8-oxodG) which can be used to estimate the oxidation of proteins, lipids and DNA, respectively. In addition, the amount of reactive oxygen species (ROS) or the antioxidant potential can be assayed (Wood et al. 2006). METHOD: Study population was composed of 4 male (18.5 ± 1.05 yr) and 4 female (17.9 ± 0.86 yr) cross-country skiers recruited from the Vuokatti-Ruka Sports Academy. The volunteers donated blood samples 8 times during their training and competition season (Aug, 2014 - Mar, 2015). ROS formation, protein carbonyl content (PCC) as well as isoprostane and 8-oxodG levels were analysed. In addition, routine clinical laboratory analytics was conducted. RESULTS: Preliminary data show that there are individual and seasonal differences in PCC, isoprostane levels and ROS formation. There is a slight increasing trend in all of the biomarker levels during the training season. A correlation was observed between different indicators of oxidative stress. Later on, the results will be correlated with other physiological markers. The changes in the oxidative stress biomarker levels appear to be at least partially connected to the training load. DISCUSSION: The study subjects had individual differences in the biomarker levels, but further studies are required to draw any conclusion on their health and training load based on these markers. It is important to note that the ROS and oxidative stress have also essential role in immune defense, cell signaling and possibly in the induction of muscle synthesis (Jackson 2008). Measuring of immediate ROS values in training would be very interesting, but it requires portable laboratory instrumentation. The study provided valuable data also for evaluation of analytical methodology. --- 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