Isokinetic knee strength profiles, conventional hamstring-to-quadriceps ratio, and performance decrement in weightlifting and wrestling athletes: a cross-sectional study

Abstract

Lower extremity strength characteristics, particularly the hamstring-to-quadriceps (H/Q) ratio and performance decrement-related variables, play a critical role in both injury prevention and athletic performance. However, few studies have compared these isokinetic knee strength characteristics according to sport type and athletic career duration. This cross-sectional study, recruited 40 weightlifting and wrestling athletes. Classified them into a <= 5-year experience group (n, 15; 20.33 +/- 1.84 years) and a >= 6-year group (n, 25; 31.40 +/- 3.51 years). Using a Biodex System IV dynamometer, bilateral knee flexion/extension peak torque was measured at angular velocities of 60 degrees/s (3 trials), 180 degrees/s (5 trials), and 240 degrees/s (26 trials), from which the H/Q ratio, explosive, and performance decrement percentage were derived. The >= 6-year career group was older than the <= 5-year group (p < 0.001), with no significant differences in other body-composition variables. Weightlifters exhibited higher H/Q ratios than wrestlers at 60 degrees/s bilaterally (right, p = 0.036; left, p = 0.015) and higher explosive ratios in right knee extension at 60 degrees/s (p < 0.001) and 180 degrees/s (p = 0.023). Career-duration groups differed significantly in right knee flexion measures, with the largest difference at 240 degrees/s average peak torque (p = 0.006). Knee strength variables were significantly correlated with strength-related factors, including performance decrement % (all p < 0.001). In this cross-sectional study, isokinetic knee strength-related characteristics varied according to sport type and athletic career duration. Regular monitoring of isokinetic strength profiles, including the H/Q ratio and performance decrement index, may help inform individualized training programs and support injury prevention strategies.