Improved respiratory muscle endurance of highly trained cyclists and the effects on maximal exercise performance

To study the effects of 4 weeks of isocapnic hyperventilation training on the respiratory muscle (RM) endurance and cycling performance, 10 highly trained male cyclists (VO₂max = 66 +. 5 ml/kg/min) were assigned to equal experimental (E) and control (C) groups. The following measurements were obtained for each subject both the hyperpnea training period: maximal sustained ventilatory capacity (MSVC), maximal oxygen consumption (VO₂max), maximal exercise ventilation (V[sub E]max), a performance cycle test at 90% VO₂max (tlim), maximal ventilation during tlim (V[sub E]tlim), Forced expiratory volume in one second (FEV₁), Forced vital capacity (FVC), and Maximum voluntary ventilation in 12 seconds (MVV₁₂). For the E group, the training consisted of three, 8 minute intervals of hyperpnea per session, 4 times a week. Following training, the MSVC of the experimental subjects increased significantly (155.4 ± 11 to 173.9 + 12 1/min; p = 0.004) with no change for the control group (155.1 ± 26 vs 149.5 ± 34 1/min, p > 0.05). VO₂max was not significantly changed for the E group (64.2 ± 1.9 vs 65.8 ± 4.8 ml/kg/min, p > 0.05) nor for the C group (68.0 ± 6.6 vs 67.1 ± 5.8 ml/kg/min, p > 0.05). Similarly, no significant differences were observed for tlim (342.2 ± 75 vs 427.8 ± 226.1 sec for the E group and 328.6 ± 99 vs 342.4 ± 80 sec for the C group, p > 0.05). There were also no significant changes for either the E group or for the C group for the measurements of V[sub E]max (177.0 ± 22 vs 177.1 ± 13 1/min; 171.4 ± 36 vs 167.5 ± 21 1/min); V[sub E]tlim (176.0 ± 16 vs 178.5 ± 19 1/min; 174.0 ± 29 vs 176.3 ± 27 1/min); FEV, (4.4 ± 0.3 vs 4.5 ± 0.4 1/; 4.8 ± 0.6 vs 4.7 ± 0.7 1); FVC (5.5 ± 0.9 vs 5.7 ± 1.0 1; 5.7 ± 0.7 vs 5.6 ± 0.7 1); or MVV₁₂ ( 205.5 ± 15 vs 216.3 ± 19 1/min; 215.2 ± 20 vs 223.3 ± 26 1/min, all p > 0.05). Results of this study indicate that the RM endurance of highly trained male cyclists can be increased following specific hyperpnea training but this does not result in changes in maximal exercise performance.Education, Faculty ofCurriculum and Pedagogy (EDCP), Department ofGraduat