What Is The Optimal Frequency For Ankle Muscles During Whole-Body Vibration Exercises?

Abstract

Usage of the whole-body vibration (WBV) is effective in preventing the ankle injuries caused by increasing neuromuscular activity. The aim of this study was to investigate effective frequencies for neuromuscular activity of ankle muscles. A single-group, repeated-measures study design was used. Twenty-three healthy subjects (age 23.91 +/- 3.07, BMI 22.66 +/- 3.39) participated in this study. This study investigated the effects of WBV on the EMG responses of the Tibialis Anterior (TA), Peroneus Longus (PL), Gastrocnemius Medial (GM) and Lateral heads (GL). The muscle activity was measured with an 8-channel EMG Noraxon MiniDTS system (Noraxon, USA, Inc, Scottsdale, AZ) during 0, 20, 40 and 60 Hz of vibration. The Physio Plate (R) vibration platform (Physio Plate (R), Domino S.R.L, San Vendemiano, Italy) was used to deliver mechanical vibration. Compared with no vibration condition; EMG activity of all ankle muscles were significantly increased from at 60 Hz (123 % in TA, 64 % in PL, 53 % in GM, 77 % in GL) (p<0.01). At 40 Hz of vibration frequency, EMG responses of GM and GL was significantly increased (27 % and 53%, respectively) (p<0.01). Only GL was significantly increased of 33 % at 20 Hz (p<0.01). It could be concluded that using higher frequencies at whole-body vibration exercises are more effective than lower frequencies on ankle muscles' EMG activities. During squat exercises on the WBV platform, higher frequencies should be used to increase ankle muscle activation.