Abstract

The purpose of this study was to examine the efficacy of closed kinetic chain exercises in preferentially recruiting the oblique fibers of the vastus medialis obliquus (VMO). Fifteen athletically active females, 6 with patellofemoral pain syndrome (PFPS) and 9 without PFPS, performed two isometric and two dynamic closed kinetic chain exercises. The isometric exercises were a static lunge with 30ø of knee flexion (SL-30ø) and with 70ø of knee flexion (SL-70ø). The dynamic exercises were a step-up/step-down exercise (SUSD) and a modified wall slide (MWS). Selective recruitment of the VMO occurred during the MWS (p<.05) and the SUSD in the subjects without PFPS (p<.05). For the SL-70ø (p<.01), the MWS (p<.01), and the SUSD (p<.05), subjects with PFPS had greater activity of the vastus lateralis (VL), resulting in a lower VMO:VL ratio for those exercises (p<.05). It was concluded that the closed kinetic chain exercises examined in this study do not preferentially recruit the VMO in individuals with PFPS. In addition, individuals with PFPS have a lower VMO:VL ratio during these exercises compared to individuals without PfPS. Verf.-Referat