Medicina Sportiva 2004 vol. 8 nr. 2

COMPLEXITY OF AN ATHLETIC FITNESS WITH RESPECT TO SELECTION AND TALENT PROGNOSIS FROM
A PHYSIOLOGICAL POINT OF VIEW*

Ulmer Hans-Volkhart
Department of Sports Physiology, FB Sport
Johannes Gutenberg-University, Mainz, Germany

Abstract
The level of an athletic fitness depends on a complex interaction of various performance-related factors. It is a common knowledge that these factors are different for each specific athletic discipline, and thus can be divided into categories that are measurable and not measurable by tests. Sport scientists often test the athletes’ fitness level. It is necessary to admonish them: Careful monitoring the results with respect to the complexity of an athletic fitness is advised.
In soccer, applying the rating scale is more accurate than testing and testing scale works better than throwing a dice. While the “False negative and false positive” decision approach is hard to avoid, the percentage of false negative decisions should be minimal. With respect to the test criteria sensitivity and specificity this is only possible by accepting a high percentage of false positive decisions in searching for talented athletes.
When subjecting individuals to adjudicating, scoring or testing, the experience is a crucial factor. Carrying out the most accurate diagnosis and prognosis of an athletic fitness can be achieved through integration of objective and subjective parameters. Since the coach’s view and experience plays a decisive role in recognizing the skills and talents of a teenage athlete, it is imperative that the coach be the judge.
Key words: fitness, coach’s view, athletes, selection, talent prognosis, assessment, soccer
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EFFECT OF LOW INTENSITY NEAR INFRARED (810 nm) LASER RADIATION
ON HUMAN ERYTHROCYTE MEMBRANE ENZYMES

Jolanta Kujawa1, Magdalena Sadowska2, Ilya B. Zavodnik3, Ewa Kilańczyk2,
Ireneusz Pieszyński4, Maria Bryszewska2
1 Department of Rehabilitation, Medical University of Lodz, Poland
2 Department of General Biophysics, University of Lodz, Poland
3 Institute of Biochemistry, National Academy of Sciences of Belarus, Grodno, Belarus
4 Department of Physical and Bio-Coordination Chemistry, Faculty of Pharmacy, Medical University of Lodz, Poland

Abstract
Objective: The exact mechanism of the influence of low-intensity laser radiation on living cells has not yet been explained.
The aim of the study was to investigate the effect of low-intensity infrared laser radiation (810 nm, 125 mW/cm2) on activity of human erythrocyte acetylcholinesterase (AChE) and (Na+, K+, Mg2+) ATPase. In this study, the dependence of activity of human erythrocyte membrane enzymes on dose of energy, density of energy, and way of dosage were performed.
Summary background data: Explanations based on the light absorption by primary endogenous chromophores have been proposed to describe biological effects of laser light on the structure of cellular membranes and are recognized to play a secondary role in the relation to those observed in mitochondria.
Methods: Human erythrocyte cell membranes were irradiated with low-intensity laser light (810 nm, 125 mW/cm2) at different continuous light doses (0-20 J) and fractionated doses (9 J and 12 J) at 37°C as the parameters characterizing the structural and functional changes of cell membranes, the activities of Na+-, K+- and Mg2+-ATPases as well as acetylcholinesterase activity (AChE) were measured.
Results: It was found that low-intensity, near-infrared laser radiation affects changes in the AChEase and ATPase activities in the dose - and way of dosage - dependent manner. At smaller doses of irradiation the activity of the enzymes slightly increased in comparison to control and reached a maximum for 9 J. The total and Na+, K+ ATPase activity after fractionated doses (3+9 J and 9+3 J) was significantly higher than for a single dose of 12 J, and significantly decreased for a dose of 3+6 J and 6+3 J with comparison to a single dose of 9 J. AChE activity after fractionated dosage of radiation changed in the opposite way. When bigger doses were applied first they induced greater stimulation of enzyme activity.
Conclusions: Low-intensity near-infrared laser radiation (810 nm, 125 mW/cm2) changed membrane enzymes activity in the dose- and way of dosage-dependent manner.
Fractionation of the light dose significantly altered the membrane response to laser radiation.
The differences of the effects of laser light on activities of both enzymes may have resulted from their different location in the membrane.
Key words: low power lasers, ATPase, acetylcholinesterase, fractionated dosage
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The effect of carbohydrate supplementation during the recovery interval on immunoendocrine responses to a repeated bout of prolonged cycling

Tzai-Li Li1, Michael Gleeson2
1 Department of Sport and Leisure Studies, National Dong Hwa University, Taiwan
2 School of Sport and Exercise Sciences, Loughborough University, Loughborough, UK

Abstract
Aim of the study: The purpose of this study was to examine the effect of carbohydrate feeding during the recovery interval (REC) separating two 90-min cycling bouts (EX1 started at 09:00 and EX2 started at 13:30) at 60% ¦O2max on leukocyte redistribution, neutrophil degranulation response to lipopolysaccharide (LPS) and plasma IL-6 and stress hormone responses to EX2.
Methods: Subjects (n = 8) consumed a 10% w/v glucose or placebo beverage (22 mL·kg-1 body mass) during the first hour of REC in two experimental trials, which were completed in a counterbalanced order and separated by at least 4 days. Venous blood samples were taken 5 min before exercise and immediately post-exercise for both trials.
Results: The main findings were that ingestion of carbohydrate compared with placebo during REC blunted the increase in the blood leukocyte count, plasma ACTH and cortisol concentrations, and total neutrophil degranulation response to LPS during EX2. Furthermore, EX2 evoked significantly higher circulating numbers of leukocytes, neutrophils, lymphocytes and monocytes, higher plasma concentrations of stress hormones, and total LPS-stimulated elastase release.
Conclusions: These findings suggest that compared with placebo, carbohydrate ingestion during REC between two bouts of prolonged exercise attenuates hypothalamic-pituitary-adrenal axis activation; however, this has only a limited effect on perturbations of circulating leukocyte subsets and neutrophil function during the second exercise bout. A second prolonged exercise bout causes a greater disturbance in immunoendocrine responses than the first exercise bout on the same day and this effect is not substantially attenuated by CHO supplementation during the recovery interval.
Key words: leukocyte redistribution, neutrophil degranulation, IL-6, stress hormones
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