The Electromyographic Activity of Lower Limb Muscles in the Elderly during Walking on the Treadmill: An Emphasis on the Effect of Virtual Reality

Abstract

Introduction: The aim of this study was to assess the effects of virtual reality (VR) on the electromyographic (EMG) activity of the lower limb muscles during gait on the treadmill in the elderly.Materials and Methods: 12 elderly male subjects participated in this study voluntarily. Using an EMG-USB2+ multichannel system (Bioelettronica, Italy) (sampling frequency of 1000 Hz) and bipolar surface electrodes, the electrical activity of tibialis anterior (TA), rectus femoris (RF), and biceps femoris (BF) muscles were recorded bilaterally during walking with the preferred speed with and without VR environment on the treadmill. The maximal voluntary isometric contraction (MVIC) method was used for the normalization of signals. The gathered signals were processed using OT BioLab software with a bandpass filter of 10-350 Hz and a notch filter of 50 Hz. The data were processed using repeated measures analysis of variance (ANOVA) and paired sample t-test in SPSS software at a significance level of 0.050.Results: The findings showed that during walking in VR environment, the EMG activity of bilateral RF muscles and right TA muscle of the elderly subjects were significantly higher than normal walking with about 1.97 (P ≤ 0.005), 1.91 (P ≤ 0.003), and 2.03 (P ≤ 0.002) times, respectively. But the differences between EMG activity of right (P ≤ 0.280) and left (P ≤ 0.990) BF and left TA (P ≤ 0.080) muscles were not significant during walking with and without VR. Overall, VR had the main effect on the muscle activity of the elderly subjects (P ≤ 0.007). Moreover, there was a significant interaction between VR and muscle factors (P ≤ 0.036).Conclusion: The results indicated that VR increases the EMG activity of lower extremity muscles among the elderly, thus it can be recommended strongly in the rehabilitation of lower extremity muscles in the elderly.

Keywords

• walking
• virtual reality
• electromyography
• elderly