Abstract
Strengthening the femoral quadriceps (FQ) muscular group is very important due to its function in moving. The joint position may generate modifications in muscle recruitment. Consequently, the objective of this study was to verify if foot position variations during knee extension are efficient in the specific selection of the rectus femoris, vastus lateralis, and vastus medialis muscles comprising the FQ. Eleven female college students (ages 22.36 ± 3.56 years old) participated in the study. Muscle activation was evaluated through surface electromyography, with bipolar configuration, in 3 series of 10 maximum repetition (MR) of bilateral knee extension, in three foot positions: neutral position, internal rotation, and external rotation. Results do not indicate significant differences among the superficial FQ muscles in all foot positions. In conclusion, results suggest that variations in foot rotation degrees during knee extension are not efficient for the specific selection of the muscles comprising FQ.
Keywords electromyographic evaluation; knee extensors; foot variation