Maintenance of hyperglycaemia does not improve perfomence in a 100 km cycling time trial

摘要: Objectives. The aim of this study was to determine whether the elevated plasma glucose oxidation rate (~ 1.8 g.min-1) in latter stages prolonged exercise subjects which hyperglycaemia (± 10 mmol.l-1) is maintained via a clamp, improves 100 km cycling time-trial (TT) performance. Design. Seven endurance-trained male cyclists (22±4 yrs) participated randomised crossover trial. On two occasions, separated by 7 - days, performed a self-paced TT laboratory. During one blood at euglycaemic concentration ± 5 mmol.l-1 (ETT) and during other, ±10 mmol.l-1 (HTT). Each interspersed with X 1 high-intensity periods (HIP) 4 HIP, an attempt mimic variable intensity competitive road races. Subjects were instructed complete ‘fastest time possible', taking 9 HIP (21 km) into consideration. Results. There were no significant differences between ETT HTT overall (143:09±7:14 v. 142:23±7:16 min:s), mean power (275±39 279±39 W) heart rate (160±9 158±11 beats.min-1). Conclusion. Time trial performance over not improved maintaining hyperglycaemic (10 concentration. South African Journal Sports Medicine Vol. 19 (3) 2007: pp. 94-98