Isokinetic Assessment of Muscular Strength and Balance in Brazilian Elite Futsal Players

Abstract

Purpose/Background: Strength asymmetries are related to knee injuries in intermittent sports players. The purpose of this study was to examine whether elite futsal players demonstrate strength asymmetries during knee isokinetic testing applying the Croisier et al. 21 criteria. Methods:Forty male elite (27.9 ± 6.5 years) Brazilian futsal players participated in the study. The testing protocol required players to perform concentric contractions of both quadriceps and hamstring muscles at angular velocities of 60°·s -1 and 240°·s -1 and eccentric contractions of hamstring at 30°·s -1 and 120°·s -1 . Conventional (concentric:concentric) and mixed (eccentric:concentric) hamstrings/quadriceps (H/Q) ratios were calculated. Subjects were determined to have an imbalanced strength profile if an athlete had at least two parameters that were asymmetrical across speeds and conditions. Asymmetry was operationally defined as peak torque asymmetry greater than 15% in bilateral comparison, and H/Q ratio less than 0.47 for conventional and 0.80 for mixed conditions. Results: Significant differences were observed between preferred and nonpreferred limbs in the concentric contractions of flexors at 240°·s -1 and eccentric contractions of extensors and flexors at 30°·s -1 and 120°·s -1 . However, these asymmetries did not exceed 15%. The conventional and mixed H/Q ratios were greater in the preferred than in nonpreferred limbs, but only the mixed hamstrings ecc /quadriceps conc in the nonpreferred limbs showed values lower than recommended (<0.80). In addition, 50% of elite futsal players had preseason strength imbalances per the developed criteria. Conclusion:The studied elite futsal players had preseason strength imbalances, which may increase the risk of hamstring injuries. Level of evidence: 3

Muscular Strength Imbalances Are not Associated with Skin Temperature Asymmetries in Soccer Players

“…Considering torque asymmetries, significant differences were observed between preferred and non-preferred limbs for hamstring concentric contractions at 240°/s and eccentric contractions at 30°/s. Similarly, bilateral asymmetries for soccer and futsal players were observed by other studies as well [ 3 , 4 , 5 , 6 , 31 , 32 ]. Ruas et al [ 31 ] showed that the preferred limb of soccer players presented higher eccentric hamstring strength than the non-preferred limb.…”

Physical and Physiological Match-Play Demands and Player Characteristics in Futsal: A Systematic Review

“…Several studies have presented that stronger and more powerful players of different modalities tend to be faster, have better COD ability, and jump higher (Wilson et al, 1993 ; Newton et al, 2006 ; Freitas et al, 2019 ). In this context, four studies (Cuadrado-Peñafiel et al, 2014 ; Vieira et al, 2016 ; De Lira et al, 2017 ; Nunes et al, 2018 ) investigated the strength capabilities of futsal players ( Table 3 ). Utilizing an isokinetic dynamometer, different authors (Vieira et al, 2016 ; De Lira et al, 2017 ; Nunes et al, 2018 ) assessed elite futsal players' strength levels by reporting peak torque values of the quadriceps and hamstrings.…”

“…In this context, four studies (Cuadrado-Peñafiel et al, 2014 ; Vieira et al, 2016 ; De Lira et al, 2017 ; Nunes et al, 2018 ) investigated the strength capabilities of futsal players ( Table 3 ). Utilizing an isokinetic dynamometer, different authors (Vieira et al, 2016 ; De Lira et al, 2017 ; Nunes et al, 2018 ) assessed elite futsal players' strength levels by reporting peak torque values of the quadriceps and hamstrings. De Lira et al ( 2017 ) reported that peak torque values at 60°·s −1 of the dominant leg were 223.9 ± 33.4 N·m for the quadriceps and 128 ± 27.6 N·m for the hamstrings, while the non-dominant leg displayed values of 224 ± 35.8 N·m and 124.1 ± 20.1 N·m −1 for the knee extensors and flexors, respectively.…”

“…The H/Q ratio was 0.58 ± 0.1. Interestingly, when the mixed H/Q ratio (i.e., hamstrings eccentric angular velocity of 30°·s −1 and quadriceps concentric velocity of 240°·s −1 ) was assessed in the preferred and non-preferred limbs of 40 players, significant contralateral differences were found on knee flexors' eccentric contractions and in the H/Q ratio in favor of the preferred limb (Nunes et al, 2018 ). Only one study assessed the one repetition-maximum (1RM) on the half-squat exercise in order to characterize futsal players' strength qualities (1RM: 94.73 ± 17.01 kg) (Cuadrado-Peñafiel et al, 2014 ).…”

“…In this context, four studies (Cuadrado-Peñafiel et al, 2014;Vieira et al, 2016;De Lira et al, 2017;Nunes et al, 2018) investigated the strength capabilities of futsal players ( Table 3). Utilizing an isokinetic dynamometer, different authors (Vieira et al, 2016;De Lira et al, 2017;Nunes et al, 2018) assessed elite futsal players' strength levels by reporting peak torque values of the quadriceps and hamstrings. De Lira et al 2017 The H/Q ratio was 0.58 ± 0.1.…”