Affiliations: [a] Physical Education School, Federal University of Rio
Grande do Sul, Porto Alegre, Brazil | [b] Department of Kinesiology, California State
University, Fullerton, CA, USA | [c] CIPER, Faculdade de Motricidade Humana, Universidade
de Lisboa, Cruz Quebrada, Portugal
Correspondence:
[*]
Corresponding author: Cassio Victora Ruas, Physical Education
School, Federal University of Rio Grande do Sul, UFRGS, Felizardo Street, 750
– Jardim Botânico, 90690-200 Porto Alegre/RS, Brazil. Tel.: +55 51 3308
5894; Fax: +55 51 3308 5843; E-mail: [email protected]
Abstract: BACKGROUND: The isokinetic hamstrings to quadriceps (H:Q)
dynamic control ratio (DCR) is frequently used to assess muscle imbalances and
to screen for potential risks of knee injuries in sports. OBJECTIVE: To investigate the correlation between knee conventional ratio (CR) and DCR in
elite soccer players and check for a possible relationship. A positive
correlation would indicate that the CR could predict DCR. METHODS: One hundred and thirteen Brazilian elite soccer players (25.2 ± 5.3 yrs)
performed maximal dominant and nondominant knee concentric (CON) and eccentric
(ECC) strength tests at 60°/s on an isokinetic dynamometer in order to
calculate CR and DCR. RESULTS: A significant positive correlation
between ratios was found for the dominant and non-dominant knees (r=0.54
and 0.62; p < 0.001 which translated into low R^{2} values of 0.29 and
0.39, respectively. CONCLUSION: This suggests that the CR may not
replace the DCR and is thus of a limited clinical value in assessing knee
muscles imbalance. On the other hand, the paper presents for the first time a
robust reference frame for the isokinetic strength and related ratios of the
two major knee muscles in soccer players.
