Comparing the Effects of Ergonomic and Standard Office Chairs on Trunk Muscle Activation

Abstract

Background and Purpose: Musculoskeletal disorders (MSD) are one of the most common health problems faced by individuals who sit for prolonged periods. The sitting design of office chairs has recently become an important aspect in preventing the MSD. The aim of this study is to determine the effect of different chair types on trunk muscle activation. Methods: Fifteen participants (age 22.92 ± 3.40 years) were included in the study. Participants’ muscle activations were assessed with the sEMG device while sitting and typing on the computer for one hour. Results: When two different types of chairs were compared, in the first 10 minutes, % MVC difference was observed only in the TES (p<0.05). Also, %MVC difference was found only in the TrA/IO (p<0.05) during the last 10 minutes. No significant difference was identified in two chair types in terms of activation of UT (p>0.05). Conclusions: It was shown that ergonomic chair may not significantly alter the activation of UT, TES, and TrA/IO muscles compared to the standard type. Therefore, the use of ergonomic chairs suitable for the physiological needs of individuals should be recommended in order to encourage increased trunk muscle activation during prolonged sitting.

Keywords

• Ergonomics
• Electromyography
• Office chairs
• Muscle Activation

References

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