1. Isokinetic and Isometric Assessment of the Knee Joint Extensors and Flexors of Professional Volleyball Players
- Author
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Lukasz Szczesny, Agata Rzepnicka, Jacek Maczynski, Jarosław Kabaciński, Piotr Wilkosz, John Ostarello, Krzysztof Maćkała, Lechosław B Dworak, Anna Fryzowicz, and Michał Murawa
- Subjects
medicine.medical_specialty ,Health, Toxicology and Mutagenesis ,Isometric exercise ,Concentric ,Knee Joint ,Article ,biomechanics ,knee joint ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,medicine ,Humans ,Knee ,030212 general & internal medicine ,Muscle Strength ,Muscle, Skeletal ,Mathematics ,isokinetics ,statics ,Public Health, Environmental and Occupational Health ,Biomechanics ,Resistance training ,volleyball ,030229 sport sciences ,musculoskeletal system ,muscle torque ,Muscle torque ,Torque ,Muscle strength ,Medicine ,human activities - Abstract
Purpose: The main objective of this study was to evaluate the level of muscle strength by using isokinetic and isometric measurements—more specifically, the force ratio between the knee flexors and extensors (values of the torques). Methods: An experimental group of elite volleyball players (n = 14) were compared to a control group (n = 14) of healthy non-athletes of comparable ages. Torque measurements were obtained under three concentric conditions (angular velocities of 60 °/s, 180 °/s, and 300 °/s) and one static condition by utilizing the Biodex System 3. Results: In all trials, the volleyball players achieved significantly higher peak torque (PT) values for both the extensors and flexors (p <, 0.05) than those of the control group. However, the strength ratio of the flexors and extensors (H/Q) in the experimental group was only 83% of the standard reported in the literature. The most developed and dominating muscles in the knee joints of the volleyball players were the extensors, which accounted for the low strength ratio and dynamic instability of this joint. Conclusion: Based on a proper assessment of the strength ratio of the knee flexors and extensors, properly selected and implemented resistance training can improve the maximum strength and power production and reduce the incidence of injuries in volleyball.
- Published
- 2021