African Journal of Pharmacy and Pharmacology Vol. 5(4), pp. 532-537, April 2011 Available online http://www.academicjournals.org/ajpp DOI: 10.5897/AJPP11.084 ISSN 1996-0816 ©2011 Academic Journals Full Length Research Paper A study on serum leptin, lipoproteins and glucose levels of judoists and cyclists of Turkey Mehmet Türkmen Yasar Dogu School of Physical Education and Sports, Ondokuzmayis University, Samsun, Turkey. E-mail: turkmenafsin@hotmail.com. Tel: +90 362 3121919/ 2790, +90 5326588027. Fax: +90 3624576000. Accepted 4 April, 2011 Fat metabolism is important for judo in weight loss and recovery and for cycling in the energy production and recovery during workouts and competitions. Leptin controls the size of fat stores by inhibiting appetite. The purpose of this study was to compare serum leptin, lipoproteins and glucose levels between male national judoists and cyclists. The subjects of this study consist of totally 61 athletes, including 24 Turkish National junior judoists and 37 senior national cyclists. The mean age, training age and body mass index (BMI) of two groups are different from each other. Both judoists and cyclists were training before international competitons. Analyses of serum lipoproteins, triglycerides, total cholesterol, LDL-cholesterol and HDL-cholesterol, were determined by an automated chemistry analyzer kits. The differences between two groups was tested by Mann-Whitney U test and the correlations among parameters was obtained from Pearson Correlation formula. There were statistically significant differences in the mean age, training experience and BMI between judoists and cyclists statistical analyzes showed no significant difference among the means of total cholesterol, triglyceride, LDL and leptin between two groups. Significant differences were observed in the mean glucose, insulin and HDL values between judoists and cyclists. Significant difference was found only at 0.01 level in the mean of insulin and at 0.05 level in other parameters. Judoists had a higher insulin, total cholesterol, triglyceride and LDL levels than the cyclists, whereas cyclists had higher values than judoists In the mean of insulin, HDL and leptin. Cyclists also had lower insulin sensitivity than judoists. In conclusion, neither judo nor cycling had an effect on leptin, LDL, triglyceride, total cholesterol level. But glucose, insulin and HDL levels were changed depending on type of sports. Key words: Judo, cycling, leptin, homeostasis model assessment, lipoproteins, insulin resistance, serum leptin, glucose levels judoists, cyclist. INTRODUCTION Judo needs the short duration, high intensity bursts of activity, and discontinuity with reactive strength and agility to respond to an opponent's strategy, whereas cycling requires endurance capacity including nonstop maximal continuous activity and working hard over a long distance, generating constant rotations per minute to maintain speed and power against the resistance of the pedals, environment, and terrain. Dominant energy systems for judo are anaerobic alactic and lactic respectively. In cycling there is only the dominance of aerobic energy system. For both sports, significant aerobic fitness is the base to make workouts and to have fast recovery after training and competitions. While cyclists have the highest aerobic endurance among all sports. Judoists perform within a moderato-level of aerobic system (Bompa and Carrera, 2005; Bompa, 2006). Carbohydrate is used as substrate in alactic and lactic anaerobic energy production systems whereas fat is used only in aerobic system from low to sub maximal intensities with long duration. Aerobic exercises increase use of free fatty acids, decreasing at the same time fat tissue of the body.The fat metabolism is important for judoists not only in losing weight, but also in refulling energy stores during recovery as well as in the preparing to the workouts in warm up. In addition, fat metabolism for cyclists is very dominant in training and competitions under maximal efforts. Plasma leptin is associated with satiety and leptin. It stimulates lipid metabolism, and