Investigation of Neuromuscular Activation in Older Female Adults during a Dynamic and Challenging Virtual Reality Activity: A Cross-Sectional Study.

Abstract

The use of virtual reality (VR) in older adults promotes improvements in mobility, strength, and balance. Changes in neuromuscular activation have been found to be associated with these improvements; however, during VR activities, this aspect has not been thoroughly investigated. The aim of this study was to investigate neuromuscular activation among older female adults during VR activities. Sixteen older female adults, with the use of VR, performed dynamic punching movements involving elbow flexion/extension for one minute, and the muscle activation of the bicep brachii was recorded with electromyography (EMG) and normalized to the maximal voluntary isometric contraction of elbow flexion. The one-minute activity was divided into three time phases: 0-10 s, 25-35 s, and 50-60 s. The five highest EMG amplitude values (%) in each phase were selected and averaged. Differences between phases were analyzed using repeated ANOVA (α_adj = 0.017). The EMG amplitude for the first phase was 39.1 ± 2.6%, that for the second phase was 44.8 ± 3.0%, and that for the third phase was 49.6 ± 3.1%. Statistically significant differences were found in all phases, with the first phase demonstrating a lower EMG amplitude (%) compared to the second (p = 0.002) and third phases (p = 0.000). The third phase demonstrated a higher EMG amplitude (%) compared to the second phase (p = 0.025). Engagement in VR activities can have significant effects on neuromuscular activation in older female adults, with our findings revealing a significant increase in the EMG amplitude within one minute of commencing a dynamic and challenging activity such as virtual boxing.