ABDOMINAL BRACING MANEVRASININ FARKLI DİZ FLEKSİYON AÇILARINDA, KUADRİSEPS ZİRVE TORKU, ZİRVE TORKA ULAŞMA SÜRESİ VE KAS AKTİVASYONU ÜZERİNE ETKİSİ

Abstract

Purpose: The aim of this study was to investigate the effects of abdominal bracing maneuver (ABM) on quadriceps peak torque (PT), time to peak torque (TTPT) and activation levels during quadriceps maximal strength testing in healthy individuals. Methods: Sixteen healthy individuals (Age: 24.63±1.67 years) participated in this study. Each participant was thought the ABM technique by a physical therapist. Surface electromyographic was used to measure internal oblique/transversus abdominis, vastus medialis, vastus lateralis and rectus femoris activation levels. Isokinetic dynamometry was used to measure quadriceps PT and TTPT during maximum isometric testing at 60° and 90° of knee flexion angles. Repeated measures of ANOVA was used to statistical analysis. Results: There was a significant angle by condition interaction for quadriceps PT (F(1,15)=5.30, p=0.04). PT values both decreased with ABM, but the decrease was greater at 60 compared to 90 degrees of knee flexion (60°: p=0.001, ES=0.68; 90°: p=0.008, ES=0.33). Quadriceps activation levels also decreased with ABM (p=0.04). Conclusion: The present study reveals that ABM could decrease the muscle activation levels and peak torque during maximal quadriceps strength testing. Investigators should examine the compensatory lumbopelvic movements during maximal quadriceps strength testing to prevent misleading by the force transmission.