Evaluación y análisis de valores de fuerza pre y post sesión en un equipo de la MLS durante la temporada y después del periodo transitorio (Evaluation and analysis of strength values assessed pre and post pitch session in an MLS team during the season and after the off season)
DOI:
https://doi.org/10.47197/retos.v61.107999Palabras clave:
Assessment; Strength; NordBord; ForceFrame; ForceDecks; Prevention; SoccerResumen
Antecedentes: En las últimas décadas las ciencias del deporte han avanzado mucho, pero las lesiones en el fútbol también han aumentado, posiblemente debido a mayores demandas competitivas. Las causas de las lesiones son multifactoriales: factores extrínsecos e intrínsecos. Es crucial enfocarse en factores modificables como la carga de entrenamiento, capacidades físicas, flexibilidad y fuerza. También es fundamental realizar evaluaciones especificas según las necesidades físicas y los grupos musculares más afectados en cada deporte. Es por ello el objetivo de este trabajo fue (1 ) Determinar los valores fuerza y potencia en un equipo de fútbol profesional de la Major League Soccer (MLS) durante una temporada, (2) Analizar los resultados de las evaluaciones realizadas en Pre y post sesión; (3) Determinar el efecto del periodo transitorio sobre la fuerza y potencia. Metodología: El estudio estuvo constituido por 22 futbolistas profesionales con una edad de 26.3 ± 3.9 años de un club de la Major League Soccer (MLS) excluyendo porteros. Se llevaron a cabo evaluaciones 6 evaluaciones de las cuales 3 fueron pre sesión y 3 post sesión de campo; valorando la fuerza excéntrica en isquiosurales en el curl nórdico usando el NordBord, fuerza isométrica máxima en aducción y abducción de cadera utilizando el ForceFrame, y potencia del tren inferior con el salto vertical con contramovimiento (CMJ) en las plataformas de fuerza ForceDecks. Resultados: Los valores de fuerza y potencia establecidos con las evaluaciones pre sesión muestran una altura de CMJ de 43.96 ± 3.92cm, en curl nórdico 382.46±67.79N (I) y 370.66±65.84N (D), en aducción de cadera 414.79±73.86N (I) y 424.02±71.88N (R), y en abducción de cadera 411.93±60.19N (I) y 420.77±60.54N (R). La comparación entre evaluaciones Pre y Post mostraron valores estadísticamente más bajos (p< 0.05) en el curl nórdico, la aducción y abducción de cadera, mientras que en el CMJ no presento cambios significativos (p=0.056). Por el contrario, después del periodo transitorio solamente el CMJ mostró valores más bajos (p< 0.05) a comparación del curl nórdico, y aducción y abducción de cadera (p˃0.05). Conclusiones: Los datos estudiados muestran valores de fuerza más bajos post sesión, excepto en la potencia expresada en la altura del CMJ. Tras el periodo transitorio, la fuerza en isquiosurales y cadera (ABD-ADD) no muestran cambios significativos, pero la altura del CMJ sí. Se sugiere realizar evaluaciones y entrenamiento de fuerza pre sesión para obtener perfiles basales precisos y maximizar las adaptaciones del entrenamiento de fuerza y potencia evitando los sesgos generados por la fatiga. También se recomienda implementar programas de entrenamiento durante el periodo transitorio para contrarrestar los efectos del desentrenamiento.
Palabras clave: Evaluación; Fuerza; NordBord; ForceFrame; ForceDecks; Prevención; Fútbol
Abstract. Background: In recent decades, sport science has advanced significantly, but injuries in football have also increased, possibly due to increased competitive demands. The reasons behind injuries are complex, involving both external and internal factors. It is crucial to focus on modifiable factors such as training load, physical capabilities, flexibility, and strength. It is also essential to perform specific assessments based on physical needs and the most injured muscle groups in each sport. Therefore, the aim of this study was to (1) determine strength and power values in a Major League Soccer (MLS) professional football team during one season, (2) analyze the results of pre- and post-session assessments, and (3) determine the effect of the transition period on strength and power. Methods: The study included 22 professional football players aged 26.3 ± 3.9 years from a Major League Soccer (MLS) team excluding goalkeepers. Six assessments were performed, of which 3 were pre-throwing session and 3 were post-throwing session, evaluating eccentric hamstring strength using the Nordic hamstring curl with the NordBord system, maximal isometric hip adduction and abduction strength using the ForceFrame, and lower limb power with the countermovement vertical jump (CMJ) on ForceDecks force platforms. Results: Strength and power values established with pre-session assessments show a CMJ height of 43.96 ± 3.92cm, in Nordic hamstring curl 382.46 ± 67.79N (L) and 370.66 ± 65.84N (R), in hip adduction 414.79 ± 73.86N (L) and 424.02 ± 71.88N (R), and in hip abduction 411.93 ± 60.19N (L) and 420.77 ± 60.54N (R). The results showed a significant decrease (P > 0.05) in the Nordic hamstring curl and both hip adduction and abduction in the post-session assessments compared to the pre-session assessments, the CMJ height did not show a significant change (p = ˃0.05). In the pre-season assessment compared to the data obtained in the pre-session assessments a significant decrease in CMJ height was found (p = ˂0.05), while the Nordic hamstring curl and both hip adduction and abduction did not show a significant decrease (p = ˃0.05). Conclusions: The data studied show lower strength values after the session, except for power expressed in CMJ height. After the transition period, hamstring and hip strength (ABD-ADD) did not show significant changes, but CMJ height did. It is suggested to perform strength assessments and strength training prior to the on-field soccer session to obtain accurate baseline profiles and maximize strength and power training adaptations, avoiding biases generated by fatigue. It is also recommended to implement training programs during the transition period to counteract the effects of detraining.
Keywords: Assessment; Strength; NordBord; ForceFrame; ForceDecks; Prevention; Soccer
Citas
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