Abstract des Autors

Purpose: The purpose of this study was to evaluate muscle strength and anaerobic power in young boys with hemophilia compared with healthy boys. Methods: Thirteen boys with severe hemophilia (H) (mean(+/-SD) age = 12.0+/-3.17 yr) and 16 control (C) boys (age = 11.9+/-2.8 yr) performed elbow and knee flexion and extension on the Biodex System II dynamometer at two angular velocities. They also performed a Wingate Anaerobic Test (WAnT) for the legs and for the arms. All H subjects received prophylactic factor VIII treatment in the 24 h pretesting, and no test was performed in the presence of hemorrhage. Results: C were consistently stronger than H in all dynamic strength measures (e.g., elbow flexors: 0.47+/-0.15 vs 0.36+/-0.08 N/m/kg for C and H, respectively, P<0.05). Anaerobic mean power was also higher in C compared with H in both upper and lower extremities (arms: 3.08+/-0.99 vs 2.22+/-0.46 W/kg for C and H, respectively; legs: 6.94+/-1.62 vs 5.54+/-1.03 W/kg for C and H, respectively, P<0.05). Upper and lower extremity strength, as well as anaerobic power, increased with age in C but not in H. By using the Godin Leisure-Time Exercise Questionnaire, H were found to be much less active, especially in intense activities, compared with C. Conclusion: Children and adolescents with hemophilia are characterized by lower muscle strength and anaerobic power compared with age-matched controls. This may be related to their lower leisure-time activity. Verf.-Referat