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Updated: Mar 21, 2026

Muscle Function Obtained with Motion Mode Ultrasound and Surface Electromyography during Core Endurance Exercise
Published on: August 25, 2022
Differences in the activation of abdominal muscles during trunk extension between smokers and non-smokers
Min-Hyung Rhee1, Laurentius Jongsoon Kim2
1Department of Rehabilitation Medicine, Pusan National University Hospital, Seo-Gu, Busan, Korea.
Background:
Many studies reported that the morbidity of the respiratory and circulatory diseases is higher among smokers than non-smokers. Some recent studies reported the effects of smoking on the musculoskeletal system. However, it is difficult to generalize the experimental environment because it is different from activities of daily living environment.
Objective:
The purpose of this study was to compare the differences in the activation of abdominal muscles during trunk extension between smokers and non-smokers.
Methods:
The subjects were 30 healthy adults (15 smokers and 15 non-smokers). The percentage of maximal voluntary isometric contraction (%MVIC) values of rectus abdominis (RA), external oblique (EO), internal oblique and transversus abdominis(IO&TrA) were measured using the surface electromyography System.
Results:
The results showed no significant differences in the %MVIC of RA and EO between smokers and non-smokers. However, the %MVIC of IO&TrA showed a significant difference between smokers and non-smokers. The %MVIC of IO&TrA of non-smokers was higher.
Conclusions:
The non-smokers showed greater activation of deep abdominal muscles than smokers did.
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