Single-joint isometric rate of torque development is not related to counter- movement jump performance in soccer players

Article type: Research Article

Authors: Wilhelm, Eurico N.^a | Radaelli, Regis^a | da Silva, Bruna G.C.^a | Botton, Cíntia E.^a | Barbosa, Rafael^a | Bottaro, Martim^b | Brown, Lee E.^c | Pinto, Ronei S.^a

Affiliations: [a] Exercise Research Laboratory, School of Physical Education, Federal University of Rio Grande do Sul, RS, Brazil | [b] College of Physical Education and Exercise Science, University of Brasília, Brasília, Brazil | [c] Department of Kinesiology, California State University, Fullerton, CA, USA

Note: [] Corresponding author: Eurico Nestor Wilhelm, Exercise Research Laboratory, School of Physical Education, Federal University of Rio Grande do Sul, Felizardo Street, 750, Jardim Botânico, CEP: 90690-200, Porto Alegre, RS, Brazil. Tel.: +55 11 51 3308 5845; Fax: +55 11 51 3308 5843; E-mail: [email protected]

Abstract: BACKGROUND AND OBJECTIVE: The quadriceps rate of torque development (RTD) is frequently used to evaluate explosive performance, but its functional meaning has been questioned. Thus, the aim of this study was to investigate if isometric quadriceps RTD correlates with multi-joint dynamic performance and if it has greater correlation with dynamic performance than with a single-joint isokinetic test in soccer players. METHODS: Thirty-nine male soccer players (age 21 ± 5 years, body mass 75 ± 7.5 kg, height 179 ± 5 cm) performed five maximal concentric knee extension isokinetic contractions at a velocity of 180°/s, followed by three maximal voluntary isometric contractions (MVIC) with knee angle of 60°, and five countermovement jumps (CMJ). The RTD was derived from MIVC over various time intervals (of 0.05, 0.1, 0.2, 0.3 seconds, and peak RTD) and CMJ height was calculated by flight time method. Pearson Product Moment Correlations were used to determine the relationships between variables. RESULTS: Absolute and relative isokinetic PT correlated positively with CMJ height (p< 0.001, r=0.513 and p=0.0007, r=0.521, respectively). However, none of the isometric RTD measures showed significant relationship with CMJ height (p> 0.05, r from −0.272 to 0.296). CONCLUSION: These results indicate that single-joint isometric RTD does not correlate with dynamic multi-joint performance. Thus, more specific tests in relation to contraction type, velocity and/or movement pattern should be used.

Keywords: Peak torque, muscle strength, muscle power, knee extension

DOI: 10.3233/IES-130513

Journal: Isokinetics and Exercise Science, vol. 21, no. 3, pp. 181-186, 2013