نوع مقاله : مقاله پژوهشی
1 استادیار، گروه بیومکانیک و آسیب شناسی ورزشی، دانشکده تربیت بدنی و علوم ورزشی، دانشگاه خوارزمی، تهران، ایران
2 دانشکده تربیت بدنی و علوم ورزشی، واحد تهران مرکزی، دانشگاه آزاد اسلامی، تهران، ایران
عنوان مقاله [English]
Background and Aim: Pyarmid and Reverse Pyramid loadings are used in resistance training to increase training load. Although physiological researches have tried to compare these two patterns, the differences between these two patterns on lower extremity joints biomechanics from injury risk have not been understood. The purpose of the present research was to compare hip and knee kinematics during squat at pyramid and reverse pyramid loading.
Materials and Methods: A total of 15 amateur bodybuilders from Karaj city voluntarily participated in five Repeated Maximum (5RM) calculation tests as well as a squat test with pyramid and reverse pyramid loading at 60%, 80%, and 100% of 5RM during three days with 48 hours interval. Hip and knee three-dimensional angles were registered with MyoMotion Noraxon motion capture system at 100 Hz frequency during squat tasks. The mean value for peak hip flexion, adduction, and internal rotation, as well as knee flexion and valgus during five squat repeats, were calculated and compared in similar loads during two kinds of pyramid and reverse pyramid loadings.
Results: The results of dependent t-test showed that peak hip flexion, adduction, and internal rotation, as well as knee flexion and valgus at similar loads, had significant increase in reverse pyramid loading compared with pyramid loading (P ≤ 0.05).
Conclusion: According to the results of the present study, since the increase in peak value of examined angles is an indicator for increase knee joint injuries, regarding the increase in these peak angles during reverse pyramid loading as compared with pyramid loading, it is suggested that coaches and amateur athletes use pyramid loading during their trainings.