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Ergonomic workstation reduces electrical activity of upper trapezius muscles, erector spinae muscles, and musculoskeletal complaints in agel fiber twisting process

  • Chandra Dewi Kurnianingtyas ,
  • I Putu Gede Adiatmika ,
  • Ketut Tirtayasa ,
  • I Wayan Surata ,


Background: Humans' role in small industries as a source of labor is still dominant, mostly manual work. The research was conducted on manual workers in small agel fiber industries in Yogyakarta. Manual work is related to human strength and endurance. Ergonomic problems often arise in manual labor, including neck pain, back pain, and leg pain called musculoskeletal disorders. Non-ergonomic working conditions also increase the electrical activity of muscles. This study aims to reduce electrical muscle activity and musculoskeletal complaints by repairing an ergonomic workstation in the agel fiber twisting process.

Methods: This research is an experimental study with 15 female subjects. The electrical activity of muscles is measured when working under conventional conditions (Period 1) and repairing an ergonomic work station (Period 2). The electrical activity of the muscles was measured using surface electromyography. Musculoskeletal complaints were measured before and after intervention with conventional conditions (Period 1) and ergonomic work station repair (Period 2). Musculoskeletal complaints were measured using the Nordic Body Map Questionnaire. The measurement data between the two periods were analyzed by using the paired samples t-test and the Wilcoxon signed-rank test.

Results: The results showed a decrease in the upper trapezius muscles' electrical activity by 35.46% and the erector spinae muscles' electrical activity by 22.43%. The average of musculoskeletal complaints decreased by 23.77%, measured after working in period 1 and period 2.

Conclusion: Ergonomic work station can reduce the electrical activity of the upper trapezius muscles, electrical activity of the erector spinae muscles, and musculoskeletal complaints in workers twisting the agel fiber rope.


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How to Cite

Kurnianingtyas, C. D., Adiatmika, I. P. . G., Tirtayasa, K., & Surata, I. W. (2021). Ergonomic workstation reduces electrical activity of upper trapezius muscles, erector spinae muscles, and musculoskeletal complaints in agel fiber twisting process. Bali Medical Journal, 10(1), 151–155.




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Chandra Dewi Kurnianingtyas
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I Putu Gede Adiatmika
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Ketut Tirtayasa
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I Wayan Surata
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