Neuromuscular Timing Activity on Ankle Musculature in Young Adults during Single and Dual-motor Tasks Accompanied with Altered Sensory Conditions

Neuromuscular timing activity on ankle musculature in young adults during single and dual-motor tasks accompanied with altered sensory conditions. Abstracts Previous literature has extensively analyzed neuromuscular patterns in various neuromuscular populations as well as during complex balance conditions that involve a secondary task. Purpose: This inquiry aims to identify whether challenging the sensory systems in young adults during single and dual-motor tasks can elicit changes in neuromuscular patterns at the gastrocnemius (GA) and tibialis anterior (TA). Methods: Our study consisted of twenty-nine healthy young adults (3 males and 25 females) with an average age of 24.3+/-2.4. Electromyography (EMG) electrodes were utilized to collect EMG data. The variables of interest include the onset of muscle contraction, the decay of muscle contraction, peak muscle activation, and duration of muscle contraction. The distinct balance tests consisted of four single and four dual-motor tasks where participants were instructed to maintain balance on a foam surface while concomitantly altering their sensory input. Results: Overall, no signific ant changes in EMG activity were demonstrated during the different tests, though some substantial alterations in EMG patterns were identified during dual-motor tasks. Fluctuations in EMG patterns during dual-motor tasks were much higher in GA than TA, with higher average onset during eyes open (p=0.01), higher decay of contraction during eyes closed (p=0.01), and longer duration of activity during eyes open with head movements (p=0.001). Conclusion: Though the invariability of EMG patterns during single tasks implies intact sensory and motor systems in young adults, the variability in EMG patterns during dual-motor tasks indicate the presence of dual-task interference, requiring additional postural mechanisms to maintain balance. Future studies should compare EMG response during dual-cognitive and dual-motor tasks and the cortical involvement during dual-motor tasks.