The purpose of this study was to analyze the influence of high-heeled shoes on the quadriceps electromyographic activity (EMG) during the sit-to-stand task. Ten healthy females (20.2±3.0 years) and 10 females with patellofemoral pain syndrome (PFPS) (21.3±3.4 years) participated in this study. The subjects performed a standardized sit-to-stand task under 3 conditions: barefoot, wearing sneakers and wearing 10 cm high-heeled shoes. The electromyographic (EMG) activity was recorded from the vastus medialis obliquus (VMO), vastus lateralis (VL) and rectus femoris (RF) muscles during the tasks using simple differential surface electrodes connected to an EMG system. To compare data between groups and tasks, the ANOVA test with repeated measures and the Tukey post hoc test were applied (p<0.05). Results demonstrated higher EMG activity for the VMO muscles during stand and sit tasks performed with high-heeled shoes in the control group. In the PFPS group, an increased EMG activity for the VL muscle during the stand task was observed, and the VMO:VL ratio decreased with the use of high heels. Results show that the use of high-heeled shoes can further increase the EMG activity of the VL muscle than the VMO in women with PFPS, a fact that may contribute to the increased joint imbalance and worsened PFPS. Therefore, the results suggest that this type of footwear should be avoided by women with PFPS.
patellofemoral pain syndrome; knee; shoes
