Each trial contained 3 matches with a 1-hr rest between match 1 and 2 and a 2-hr rest between match 2 and 3. A match contained 3 exercise periods lasting 2 minutes each with a work to rest ratio of 10 seconds: 20 seconds. After each exercise period, a 2 minute rest period was provided before the next exercise period. The load was 0.1 kp/kg body weight. The subjects were asked to pedal as fast as possible with vocal encouragement by research personnel. In the rest periods the load was removed and the subjects were asked to pedal at 60 rpm. The peak and average power of each sprint was recorded. Blood sample collection Blood samples were collected via an indwelled

cannula (20G). The cannula was frequent flushed by sterilized saline to keep it patent throughout the experiment. Ten milliliters of blood sample were collected into an EDTA tube at each sampling time. Hematological analysis was performed ABT-263 price immediately after the samples were taken. Thereafter, the rest samples were centrifuged at 1500 × g (Eppendorf 5810, Hamburg, Germany) to extract plasma. The aliquoted plasma samples were stored at -70°C

before analysis. Biochemical and hormone measurements The research personnel who conducted the analysis were blind to the group of the samples. Hemoglobin concentration and hematocrit in whole blood was measured JPH203 chemical structure by a hematology analyzer (KX-21N, Sysmex Corporation, Kobe, Japan) to correct for the change in plasma volume [27]. Plasma NOx concentration was measured with modified Griess reaction using a commercial kit (Sigma, St. Louis, MO, USA). The absorbance at 540 nm was Cytidine deaminase measured with a microplate spectrophotometer (Benchmark Plus, Bio-Rad, Hercules, CA, USA). Plasma concentrations of insulin were measured by electrochemiluminescence (Elecsys 2010, Roche Diagnostics, Basel, Switzerland) with the kit provided by the manufacturer. Plasma glucose, glycerol and non-esterfied fatty acid (NEFA) were measured with an automatic analyzer (Hitachi 7020, Tokyo, Japan) using commercial kits (Randox, Antrim, UK). Statistical analysis All values were expressed as means ± SEMs. The area under

the curve (AUC) was calculated for plasma concentrations of glucose and insulin, as well as total carbohydrate and fat oxidation, during the 2-hr recovery period after the second match. The changes in exercise performance, plasma concentrations of metabolites, and substrate oxidation rates were analyzed by a two-way analysis of variance with repeated measures. If the treatment or interaction effect was significant, the differences among the 3 trials at the same time point were identified by post hoc Bonferroni test. The AUC and total carbohydrate and fat oxidation were analyzed by a one-way analysis of variance with repeated measures. If the main effect was significant, the differences among the 3 trials were identified by post hoc Bonferroni test. The analysis was performed with SPSS for Windows 15.0 (SPSS, Chicago, IL, USA).