Resumen de Whole-Body-Vibration-Induced Increase in Leg Muscle Activity During Different Squat Exercises
Sabine M. P. Verschueren, Oron Levin, Machteld Roelants, Valère Stijnen, Christophe Delecluse
Roelants, M., S.M.P. Verschueren, C. Delecluse, O. Levin, and V. Stijnen. Whole-body-vibration-induced increase in leg muscle activity during different squat exercises. J. Strength Cond. Res. 20(1):124-129. 2006.-This study analyzed leg muscle activity during whole-body vibration (WBV) training. Subjects performed standard unloaded isometric exercises on a vibrating platform (Power Plate): high squat (HS), low squat (LS), and 1-legged squat (OL). Muscle activity of the rectus femoris, vastus lateralis, vastus medialis, and gastrocnemius was recorded in 15 men (age 21.2 ± 0.8 years) through use of surface electromyography (EMG). The exercises were performed in 2 conditions: with WBV and without (control [CO]) a vibratory stimulus of 35 Hz. Muscle activation during WBV was compared with CO and with muscle activation during isolated maximal voluntary contractions (MVCs). Whole-body vibration resulted in a significantly higher (p < 0.05) EMG root-mean-square compared with CO in all muscle groups and all exercises (between +39.9 ± 17.5% and +360.6 ± 57.5%). The increase in muscle activity caused by WBV was significantly higher (p < 0.05) in OL compared with HS and LS. In conclusion, WBV resulted in an increased activation of the leg muscles. During WBV, leg muscle activity varied between 12.6 and 82.4% of MVC values.
