The validity of surface electrodes to record latissimus dorsi activity during submaximal trunk movement and stability...

The latissimus dorsi, a large superficial muscle connecting the pelvis, trunk and humerus, has the potential to contribute to trunk movement and stability. Surface electrodes are most typically used to record latissimus dorsi muscle activity during trunk tasks. However, there is the risk of crosstalk from nearby muscles, potentially leading to inaccurate muscle activity estimations. Therefore, this study aimed to determine the validity of using surface electrodes to record latissimus dorsi activity levels during submaximal trunk tasks by comparing the readings to indwelling electrodes simultaneously recorded at the same location.

Thirteen asymptomatic participants had indwelling electrodes inserted below the inferior angle of the scapula and surface electrodes placed over the same location. The participants completed submaximal trunk movements and stability tasks in various positions.

There were no significant differences in latissimus dorsi activity recorded between surface and indwelling electrodes in all submaximal trunk movement tasks. However, during the trunk stability tasks the surface electrodes recorded significantly higher activity than the indwelling electrodes.

Surface electrodes are recommended as a valid option to record latissimus dorsi activity during submaximal trunk movement tasks. For tasks that challenge trunk stability, indwelling electrodes are recommended to avoid crosstalk from underlying muscles.