Muscle strength imbalance can be an important factor in hamstrings muscle strain. A hamstrings/quadriceps (H/Q) strength ratio based on concentric peak torque values (H_con:Q_con) has traditionally been used to describe the potential for knee-joint destabilization. Because certain standard actions in soccer are explosive, the analysis of the H/Q strength ratio based on the rate of torque development (H_rtd:Q_rtd) might also be useful in the evaluation of joint stability. The objective of this study was to compare the H_rtd:Q_rtd between professional soccer players with heterogeneous values of H_con:Q_con. Thirty-nine professional soccer players took part in the following procedures on different days: 1) Familiarization session with the isokinetic dynamometer, and 2) Two maximal isometric actions and five maximal concentric actions at 60°·s^-1 for hamstrings (H) and quadriceps (Q). Participants were ranked according to their H_con:Q_con ratio. The median third was excluded to form a high torque group (HTG), and a low torque group (LTG). Peak isometric (H) and concentric (H and Q) torques and rate of torque development (H) were significantly greater in the HTG group. Similarly, H_con:Q_con (0.68 ± 0.02 vs. 0.52 ± 0.03) and H_rtd:Q_rtd (0.54 ± 0.12 vs. 0.43 ± 0.16) were significantly greater in the HTG group than in the LTG group. There was no significant correlation between H_con:Q_con and H_rtd:Q_rtd. It can be concluded that H_con:Q_con and H_rtd:Q_rtd are determined, but not fully defined, by shared putative physiological mechanisms. Thus, the physiologic and clinical significance of H_con:Q_con and H_rtd:Q_rtd to an athlete’s individual evaluation might be different.

• Soccer players with high (0.66-0.70) and low (0.50-0.54) conventional concentric hamstrings:quadriceps ratios (H:Q) tend to demonstrate similar profiles (i.e., high and low, respectively) in their rate of the torque development H/Q ratio (H:Q).

• The lack of a significant relationship between H:Q and H:Q suggests that these ratios are determined, but not fully defined, by shared putative physiological mechanisms.

• Preseason screening programs that monitor hamstrings:quadriceps ratios should recognize that the physiologic and clinical significance of H:Q and Hrfd:Qrfd to an athlete’s individual evaluation might be different.