Browsing by Author "Jorga, Vladimir (6506369922)"

Regular training has been claimed to increase the activity of antioxidant enzymes and, consequently, augments the resistance to oxidative stress; however, large volumes of training performed by elite sportsmen could lead to a chronic oxidative stress state. The aim of our study was to assess the oxidative status of elite athletes at the beginning of the preparatory and the beginning of the competition training phases, so that the influence of three months of programmed physical activity on redox status could be determined. The chronic effects of exercise on the redox state of the athletes were compared to the effects of a single bout of karate training. Thirty elite karate athletes, 16-30 years old, were subjected to maximal graded exercise test to estimate their aerobic capacity; blood sampling was also performed to measure levels of superoxide anion radical (O2-), hydrogen peroxide (H2O2), superoxide dismutase activity (SOD) and catalase activity (CAT). The only significant change after the three-month training process was found in the significantly decreased CAT activity (X ± SE: 7.95 ± 0.13 U/g Hb × 103 in the preparatory period, 6.65 ± 0.28 U/g Hb × 103 in the competition stage; P < 0.01). After a single karate training session, there was statistically significant decrease of O2- (X ± SE: 32.7 ± 4.9 nmol/ml in the preparatory period, 24.5 ± 2.5 nmol/ml in the competition stage; P < 0.05) and increase of H2O2 (X ± SE: 11.8 ± 1.0 nmol/ml in the preparatory period, 14.2 ± 0.9 nmol/ml in the competition stage; P < 0.01), as well as significant CAT increase (X ± SE: 6.6 ± 0.6 U/g Hb × 103 in the preparatory period, 8.5 ± 0.5 U/g Hb × 103 in the competition stage; P < 0.05). Although the three-month training process induced, at the first sight, negative changes in the redox state, expressed through the decrease in CAT activity, adequate response of the antioxidant system of our athletes to acute exercise was preserved. © 2012 by The Chinese Physiological Society and Airiti Press Inc.

Regular training has been claimed to increase the activity of antioxidant enzymes and, consequently, augments the resistance to oxidative stress; however, large volumes of training performed by elite sportsmen could lead to a chronic oxidative stress state. The aim of our study was to assess the oxidative status of elite athletes at the beginning of the preparatory and the beginning of the competition training phases, so that the influence of three months of programmed physical activity on redox status could be determined. The chronic effects of exercise on the redox state of the athletes were compared to the effects of a single bout of karate training. Thirty elite karate athletes, 16-30 years old, were subjected to maximal graded exercise test to estimate their aerobic capacity; blood sampling was also performed to measure levels of superoxide anion radical (O2-), hydrogen peroxide (H2O2), superoxide dismutase activity (SOD) and catalase activity (CAT). The only significant change after the three-month training process was found in the significantly decreased CAT activity (X ± SE: 7.95 ± 0.13 U/g Hb × 103 in the preparatory period, 6.65 ± 0.28 U/g Hb × 103 in the competition stage; P < 0.01). After a single karate training session, there was statistically significant decrease of O2- (X ± SE: 32.7 ± 4.9 nmol/ml in the preparatory period, 24.5 ± 2.5 nmol/ml in the competition stage; P < 0.05) and increase of H2O2 (X ± SE: 11.8 ± 1.0 nmol/ml in the preparatory period, 14.2 ± 0.9 nmol/ml in the competition stage; P < 0.01), as well as significant CAT increase (X ± SE: 6.6 ± 0.6 U/g Hb × 103 in the preparatory period, 8.5 ± 0.5 U/g Hb × 103 in the competition stage; P < 0.05). Although the three-month training process induced, at the first sight, negative changes in the redox state, expressed through the decrease in CAT activity, adequate response of the antioxidant system of our athletes to acute exercise was preserved. © 2012 by The Chinese Physiological Society and Airiti Press Inc.

Background/Aim. Oxidative stress is a state of disturbed balance between reactive oxygen species (ROS) and reactive nitrogen species (RNS) on the one hand, and antioxidative defense on the other. As a result of oxidative stress we have irreversible changes in cell function leading to pathological tissue changes, development of many diseases and fast aging process. Increased consumption of oxygen during exercise could be the cause of oxidative stress. The aim of the study was to establish oxidative status of elite karate athletes in the state of rest and after the loading, monitoring the parameters of oxidative stress and components of antioxidative defense in a treaining process. Methods. During training process, a group of 30 elite karate athletes was included in the study of prevalence. They were males, from 16 to 30 years of age. The examination was conducted both in resting condition and after the loading. Oxidative status was determined by the level of superoxide anion radical (O2-), hydrogen peroxide (H2O2) as prooxidants, and enzymes of the antioxidant defanse system: superoxide dismutase (SOD) and catalase (CAT). Resusts. There was a homogenous group of young athletes of normal weight and fats percentage. A significant decrease of O.2- after the load was founded, while the levels of H2O2 was significantly increased. Activity of SOD was not significantly changed after exsercise while that of CAT was significantly increased. Conclusion. In the long run a programmed physical exercise does not lead to oxidative stress, but an excessive physical load may cause its occurrence.