Assessment of incidence of task specific brachioradialis fatigue among students..

Abstract

Background:The aim of the study is to assess the incidence of the task specific brachioradialis muscle fatigue among the students with the use of Electromyography (EMG). As the increasing academic demands on the students, repetitive upper limb task such as writing may lead to the localized muscle in the elbow flexion activity and also used as forearm stabilization. It was targeted muscle for the fatigue assessment.

A total of 82 students were participated. In this study the electrodes were placed on the brachioradialis muscle of the forearm to measure the activity during the standardized repetitive task. EMG amplitude was recorded at 1 min and 5 min and the percentage change in amplitude was calculated to quantify the fatigue.

Objective-To assess the incidence of task-specific brachioradialis muscle fatigue among students during prolonged writing tasks using surface electromyography (EMG), and to determine the changes in muscle activation between 1-minute and 5-minute writing durations.

Materials and Method : This study assessed task-specific brachioradialis muscle fatigue among 81 physiotherapy students in Karad using questionnaires and physical assessments, based on a reported 21% prevalence. This cross-sectional observational study was conducted among 81 students from Krishna College of Physiotherapy, Karad, selected using simple random sampling. Students aged 18–25, both right- and left-handed, were included. The sample size was determined using the formula:

A structured questionnaire and physical assessment, including palpation, sustained contraction, resisted elbow flexion, and VAS for discomfort, were used to identify brachioradialis muscle fatigue. Data collection was performed under controlled conditions during school hours, ensuring ethical considerations like informed consent and confidentiality. Surface electromyography (SEMG) was used where available for objective fatigue measurement.

Results-The study found a significant 21.8% reduction in brachioradialis EMG amplitude from 1 to 5 minutes of continuous writing, indicating clear task-specific muscle fatigue among students. Most participants demonstrated measurable fatigue regardless of hand dominance or forearm girth. The paired t-test showed this decline to be highly significant (p < 0.001). These findings suggest that even short periods of sustained writing can induce noticeable forearm muscle fatigue in young adults.

Conclusion- The study concludes that prolonged writing leads to a significant decline in brachioradialis muscle activity, indicating clear task-specific fatigue among students. This fatigue occurs irrespective of hand dominance or forearm girth. The findings highlight the need for ergonomic measures and periodic rest breaks during extended writing tasks.