Effects of respiratory muscle endurance training on wheelchair racing performance in athletes with paraplegia: A pilot study

Objective: Respiratory muscle endurance training (RMET) has been shown to improve both respiratory muscle and cycling exercise endurance in able-bodied subjects. Since effects of RMET on upper extremity exercise performance have not yet been investigated, we evaluated the effects of RMET on 10-km time-trial performance in wheelchair racing athletes. Design: Pilot study, controlled before and after trial. Setting: Spinal cord injury research center. Participants: 12 competitive wheelchair racing athletes. Interventions: The training group performed 30 sessions of RMET for 30 min each. The control group did no respiratory muscle training. Main Outcome Measurements: Differences in 10-km time-trial performance pre- versus postintervention. Results: In the training group, the time of the 10-km time-trial decreased significantly from before versus after intervention (27.1 +/- 9.0 vs. 24.1 +/- 6.6 min); this did not occur in the control group (23.3 +/- 2.8 vs. 23.2 +/- 2A min). No between groups difference was present (P = 0.150). Respiratory muscle endurance increased significantly within the training group (9.1 +/- 7.2 vs. 39.9 +/- 17.8 min) and between groups, but not within the control group (4.3 +/- 2.9 vs. 6.6 +/- 7.0 min) before versus after intervention. Conclusion: There was a strong trend, with a large observed effect size of d = 0.87, towards improved performance in the 10-km time-trial after 6 weeks of RMET.