Laboratory of Sport Biomechanics, Federal University of Minas Gerais, Belo Horizonte, BRAZIL.
The Journal of Strength and Conditioning Research (Impact Factor: 1.8). 07/2012; DOI: 10.1519/JSC.0b013e318265a3c8
Source: PubMed

ABSTRACT Assessment of lower extremity bilateral asymmetries in soccer players is important for both injury prevention and performance. The purpose of this investigation was to compare isokinetic knee extensor assessment of asymmetry with a more specific countermovement jump (CMJ). Forty-six male Brazilian professional soccer players participated in this study. The maximal power, maximal force and impulse were determined during CMJ as well as the total work and peak torque at 60/s, 180/s and 300/s during isokinetic leg extension, separately for each leg. Factor analysis was performed for all investigated variables, and the diagnostic concordance between different criteria was analyzed by McNemar's Chi test. The factor analysis showed that the isokinetic and CMJ tests were widely independent methods for the assessment of bilateral differences. Concordance of the diagnostic information could only be found between the maximal force during CMJ and the total work and peak torque at 180°/s and 300/s during isokinetic leg extension. Impulse and maximal power during countermovement jump on a double force platform appear to be appropriate additional variables for the identification of bilateral differences. Therefore, it might be pertinent to perform, in addition to isokinetic assessment, a vertical jump test on a force platform to assure widespread and reliable diagnostic information.

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Jun 4, 2014