Reliability of Measuring Lower-Limb-Muscle Electromyography Activity Ratio in Activities of Daily Living With Electrodes Embedded in the Clothing

Abstract

Context: Using technical clothes with electrodes embedded in the clothing makes it possible to record the electrical activity produced by the activity of the skeletal muscles in activities of daily living. Objective: To investigate the reliability of measuring lower-limb left-right electromyography (EMG) activity ratio with smart shorts during stair descent, stair ascent, and repeated unloaded squats among healthy working-aged subjects. Methods: Seventeen females (mean age 25.5 y), and 17 males (mean age 29.9 y) participated in this test-retest protocol carried out twice on the same day. Results: Intraclass correlation coefficient (ICC) varied from .65 to .80 in the different activities. Mean difference and limits of agreement (LOA) between the repeated measurements were for descending stairs –0.8%, LOA –6.2% to 4.7%; for ascending stairs –0.9%, –6.5% to 4.7%; and for squats –0.2%, –5.4% to 4.9%. The coefficient of repeatability for descending stairs was 5.6%, for ascending stairs 5.7%, and for squats 5.3%. Conclusions: Our study among healthy subjects showed that the left-right EMG activity ratio in activities of daily living can be reliably measured with smart shorts. In future research, the feasibility of technical clothes as a follow-up method in rehabilitation should be investigated in greater detail.