ANALYSIS OF ISOKINETIC KNEE EXTENSION/FLEXION STRENGTHS IN TURKISH SUPER LEAGUE SOCCER PLAYERS

Abstract

This study was designed to contribute in determining normative levels for isokinetic strength regarding knee extensor/flexor muscles and to investigate lower extremity asymmetries in isokinetic strength of Turkish Super League soccer players. A total of 153 professional soccer players (age 25.2 ± 4.1 years; height 180.9 ± 6.2 cm; body weight 77.7 ± 6.8 kg) were studied. The isokinetic strength of knee flexors (hamstrings: H) and knee extensors (quadriceps: Q) was measured using an isokinetic dynamometer at angular velocities of 60, 180, 240 and 300°/s, in the concentric mode. H/Q strength ratios were computed. A flexion deficit more than 10% was found in 34 subjects (22.2%) and a flexion deficit more than 15% was found in 11 subjects (7.2%). A total of 31 subjects (20.3%) had an extension deficit of more than 10% and nine subjects (5.9%) had an extension deficit of more than 15%. The number of subjects who had more than 10% deficits for both flexion and extension was 13 (8.5%). Of the 153 subjects, only two (1.3%) revealed both flexion and extension deficits of more than 15%. Lower extremity asymmetries were not rare in this specific group. This observation is important, as eliminating deficits may reduce injury risk in soccer players. Results will also contribute to determining normative isokinetic strength levels in Turkish Super League soccer players.