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Peroneal muscle activity during stable and unstable load exercises. A cross-sectional study
Jacobo Rodríguez-Sanz1, Luis Llurda-Almuzara2, Carlos López-de-Celis3
1Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya. Carrer de Josep Trueta, 08195, Sant Cugat del Vallès, Barcelona, Spain; ACTIUM Anatomy Group. Carrer de Josep Trueta, 08195, Sant Cugat del Vallès, Barcelona, Spain.
Unstable loads increase peroneus longus muscle activity during single leg stance exercises. However, for other exercises like Romanian deadlifts or lunges, load stability did not significantly alter muscle activation.
Area of Science:
- Biomechanics and Exercise Physiology
- Musculoskeletal Adaptations to Training
Background:
- The peroneus longus muscle plays a crucial role in ankle stability and foot eversion.
- Understanding muscle activation patterns during different loading conditions is vital for optimizing training programs and injury prevention.
Purpose of the Study:
- To compare the muscle activity of the peroneus longus during unstable load exercises versus stable load exercises.
- To investigate the influence of load type (unstable vs. stable) on peroneus longus activation across various functional movements.
Main Methods:
- A cross-sectional study was conducted involving 28 healthy athletes.
- Surface electromyography (sEMG) was used to measure peroneus longus muscle activity.
- Exercises included isometric single leg stance, single-leg Romanian deadlift, front rack forward lunge, and lateral lunge, performed with unstable (water tank) and stable (sandbag) loads.
Main Results:
- A significant interaction between load type and exercise time was observed for Root Mean Square (RMS) of muscle activity.
- The isometric single leg stance with an unstable load demonstrated significantly higher peroneus longus RMS compared to a stable load.
- Within the stable load condition, the single-leg Romanian deadlift elicited higher peroneus longus RMS than the isometric single leg stance.
Conclusions:
- Unstable load during a single leg stance exercise significantly enhances peroneus longus muscle activity compared to stable loads.
- No significant differences in peroneus longus muscle activity were found between unstable and stable loads for the single-leg Romanian deadlift, front rack forward lunge, and lateral lunge.
- The single-leg Romanian deadlift with a stable load induced greater peroneus longus activation than the isometric single leg stance with a stable load.
