Differences in Fatigue of Muscles around the Neck Depending on Task Concentration

Purpose: This comprehensive study aims to thoroughly investigate the effects of task concentration on neck muscle fatigue, with a particular emphasis on understanding the potential adverse effects on forward neck posture.This issue is increasingly prevalent among modern individuals, especially those who frequently engage with digital devices in their daily lives.Methods: Twenty healthy individuals in their 20s were fitted with electromyography(EMG) electrodes on the sternocleidomastoid and trapezius muscles.They undertook two tasks: (1) the Stroop test, which induces a high level of concentration, and (2) a letter-reading task with matching colors, which requires low concentration.Muscle fatigue was quantified using the reference voluntary contraction method and the median frequency parameter representing the average frequency component in the EMG signal analysis.Results: The analysis revealed a substantial disparity in muscle fatigue levels between the two task groups (p< 0.05).The upper trapezius muscles exhibited significantly higher fatigue levels during the high-concentration task compared to the lower concentration task (p< 0.05).This finding strongly suggests that tasks demanding higher concentration levels induce more pronounced muscle fatigue. Conclusion:The findings conclusively indicate that tasks requiring high concentration levels may contribute to increased neck muscle fatigue over time, potentially exacerbating forward neck posture issues.This study underscores the critical importance of understanding how cognitive demands can influence physical posture and muscle fatigue, with significant implications for developing strategies to effectively mitigate musculoskeletal disorders associated with extensive modern device usage.