title: Oxidative stress and antioxidant status response of handball athletes: implications for sport training monitoring.
abstract: The chronic exposure to regular exercise training seems to improve antioxidant defense systems. However, the intense physical training imposed on elite athletes may lead to overtraining associated with oxidative stress. The purpose of the present study was to investigate the effect of different training loads and competition on oxidative stress, biochemical parameters and antioxidant enzymatic defense in handball athletes during 6-months of monitoring. Ten male elite handball athletes were recruited to the study. Blood samples were collected four times every six weeks throughout the season. During most intense periods of training and competitions there were significant changes in plasma indices of oxidative stress (increased TBARS and decreased thiols). Conversely, chronic adaptations to exercise training demonstrated a significant protective effect against oxidative stress in erythrocyte (decrease in TBARs and carbonyl group levels). Erythrocyte antioxidant enzyme activities were significantly increased, suggesting a training-induced antioxidant adaptation. Biomarkers of skeletal muscle damage were significantly increased during high-intensity training period (creatine kinase, lactate dehydrogenase and aspartate aminotransferase). No significant changes were observed in plasma IL-6, TNF-α and uric acid, whereas a significant reduction was found in the IL-1β concentration and gamma-glutamyl transferase activity. Oxidative stress and antioxidant biomarkers can change throughout the season in competitive athletes, reflecting the physical stress and muscle damage that occurs as the result of competitive handball training. In addition, these biochemical measurements can be applied in the physiological follow-up of athletes.
authors.affiliation: Metodista University of São Paulo, São Bernardo do Campo, São Paulo, Brazil. douglas.marin@metodista.br
authors.forename: Douglas Popp
authors.initials: DP
authors.lastname: Marin
authors.forename: Anaysa Paola
authors.initials: AP
authors.lastname: Bolin
authors.forename: Thais Regina
authors.initials: TR
authors.lastname: Campoio
authors.forename: Beatriz Alves
authors.initials: BA
authors.lastname: Guerra
authors.forename: Rosemari
authors.initials: R
authors.lastname: Otton
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000328:Adult; D000818:Animals; D056352:Athletes; D054874:Athletic Performance; D015415:Biomarkers / Q000378:metabolism; D015444:Exercise / Q000502:physiology; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000293:injuries / Q000378:metabolism* / Q000473:pathology; D018384:Oxidative Stress; D055815:Young Adult
chemical_list: D015415:Biomarkers
keywords: Exercise; Free radicals; Inflammation; Muscle damage; Sports