1. Relations Between Performance and Physiological Parameters For Tennis Players Tolga Akşit 1, Emine Kutlay 1, Faruk Turgay 1, M. Zeki Özkol 1, Faik Vural 1 1 Ege University School of Physical Education and Sport, Coaching Education Department Abstract Introduction Methods Results and Discussion Conclusion References In this study, which aims at examining the effects of some physiological parameters on performance in the branch of tennis, by developing an exercise model on court, the relations between performance percentage, LA and GL parameters of tennis players (n=20) have been studied. In our model, groundstoke were performed which reached a maximum by gradually increasing and consisted of 4 intermittent periods; and shot accuracy percentage was defined as performance. After each period, relations between parameters determined and performance have been analysed. During this exercise model which is considered to simulate tennis due to its intermittent nature, there is a negative relation between tennis and LA elimination. Key Words: tennis, performance, physiology, lactate Test protocol applied on tennis court basal La and GL levels of subject have been determined with the fingertip blood. After a 10-minute-warm up on court, the first 3 periods were arranged to last 4 minutes and the last period 2 minutes; groundstrokes performance test has been carried out. 90- second-brakes have been taken in each period and in these breaks, LA and GL levels of the subjects were determined by fingertip blood. Telemetric heart rate monitor has recorded the subjects’ HR during the test. Groundstrokes performance test pattern shots in periods have been hit in the following order: a) Forehand parallel b) Backhand parallel c) Forehand cross d)Backhand cross. The relations between blood parameters and tennis performance have been carried out using ‘Pearson r’ correlation analysis. In relations between blood LA and GL values, ‘Pearson r’ correlation analysis has been used. For all statistical analyses "SPSS 12.0" statistics programme (SPSS Inc, Chicago, IL) has been used. Values of p<0.05 and p<0.01 have been taken as significant. The study was carried out upon the approval of Ege University Faculty of Medicine, Ethics Committee. Tennis is basically classified as an anaerobic activity. Rallies last approximately 7-10 seconds. In studies researching the contribution of glycolitic system, average blood lactate levels (LA) are around 3-4 mmol/l in good trained tennis players. Here energy is supplied by anaerobic glycolitic process. As for relaxation periods, aerobic energy system helps regeneration (1). In this study, by developing an exercise model which we think partially represents the physiological characteristics of a tennis match, we aim at analysing the relations between performance, LA, GL, HR parameters on court in regularly trained elite male tennis players between the ages of 20-30. The relations between LA -GL values taken from fingertip blood after each period and regeneration and performance percentages and heart rates following each period have been analysed In our study physical parameters; parameters such as age, body fat ratio (BFR) and body mass index (BMI) have been measured. At the end of each period, while LA, GL and HR have showed a significant and linear increase, performance percentages had decrease on the contrary. After the exercise, following levels have been measured;HR=196, blood LA value 11,2 mmol/l. These measurements show that this exercise model is an intermittent maximum one whose rate gradually increases (2-3). There is a relation between the increasing blood LA values and the decrease in the performance of technical moves. However, because of the sufficient relaxation periods between rallies and games, LA levels increasing to these levels might not be expected (1). As seen here, different LA levels can be observed during a tennis match depending on its length and pace. This shows us the fact that glycolytic system contributes at various levels during tennis matches. No significant relation has been found between PY and LA values at the end of each exercise period. Smekal and his colleagues have not found a significance difference in terms of LA concentration (4). While planning trainings for tennis players, LA levels should be taken into consideration. It is extremely important to keep the LA levels low and to provide relaxation for players in technical trainings (( Figure 1. Design of the study. 1.Kovacs M.,S. (2007). Tennis Physiology: Training the Competitive Athlete, Sports Med, 37(3):189-198. 2.Bergeron M.,F., Maresh C.,M., Kraemer V. et al. (1991).Tennis: a Physiological Profile During Match Play, IntJ. Sports Med, 12: 474-479. 3.König D., Hounker M., Schmid A.et al (2000). Cardiovascular Metabolic and Hormonal Parameters in Professional Tennis Players, Med Sci Sports Exerc, 33:654–8.. Table 1: Blood; LA, GL levels of the players (av. ± ss). Figure 2: HR (beats/min) values of the players during test (av. ±ss). Figure 3: LA values of the players during test (av. ± ss) (mmol/L). MATS: Number of balls thrown by the ball machine, TTS: total number of balls hit the target by the players group, BD: success and failure percentages. Table 2: Tennis performance values of the players (av. ± ss). p>0.05 Table 3: I. period PY, LA, GL, HR of the players and correlation analyses results of values. PY: Performance percentage, LA: lactate, GL: blood glucose, HR: heart rate, In the analyses of the relation between performance and LA, GL and HR parameters in the I. Period, no s In the exercise model in our study, LA blood values have been measured to be 4.1 mmol/l in the first period; 11.2 mmol/ in the last one while HR in the same periods has been found to be 153 and 196 respectively.