Arquitectura muscular y momento de fuerza: relación en el erector espinal durante extensión isométrica máxima

Aim

To study the relationship existing between pennation angle, muscle thickness and moment of force in the erector spinae (ES) muscle during maximal isometric extension.

Material and methods

A cross-sectional study was conducted in 46 healthy participants (25 women and 21 men) without musculoskeletal disorders. They performed 3 5-second long maximum isometric contractions in lumbar extension at 45° from vertical. During the test, moment of force and the 2 muscle architectural variables of the ES muscle were recorded. The variables obtained through ultrasound imaging (architectural variables) were considered as independent variables and torque as dependent variable in linear regression and bivariate correlation made between the variables studied.

Results

An R² value of 0.805 was obtained in the linear regression between variables. In the bivariate correlation, all the architectural variables were statistically significant between them.

Conclusion

During a lumbar extension at 45° from the vertical, the 2 independent variables (angle of pennation and muscle thickness) obtained of the ES muscle achieved an R² value higher than 0.8 on the linear regression analysis. This would explain the very high relationship between these and the dependent variable (torque).