Normative Data of Flexo-Extension of the Knees, With Agonist/Antagonist Ratio

Introduction: Knee injuries are one of the most frequent injuries in sport. So, it reveals the most serious health problems, whatever the age, and in almost every sport. Isokinetic and isometric assessments have been demonstrated to be accurate strength measurements of knee flexion and extension. The strength ratio between the hamstring and the quadriceps are commonly used to describe the dynamic stability of the knee. The conventional index is the most widely reported ratio in scientific literature, and it is estimated by dividing the maximum couple of the hamstring by the one of the quadriceps, on concentric/concentric form. A ratio of 0.6 at a speed of 60°/s, is considered to represent normal knee function. A strength imbalance greater than 10-15% of the bilateral index through an isokinetic test FR/ERCON60° could indicate that the rehabilitation program was unsuccessful, which prevents sportsmen to train and/or compete safely. For the professional football players, we can define as normal a value of 0.47 for the strength index FR/ERCON60°. In the literature, differences in isometric and isokinetic strength have been demonstrated between genders, with: women achieve 55.9% to 63.0% of the men's values.

Introduction: Knee injuries are one of the most frequent injuries in sport. So, it reveals the most serious health problems, whatever the age, and in almost every sport. Isokinetic and isometric assessments have been demonstrated to be accurate strength measurements of knee flexion and extension. The strength ratio between the hamstring and the quadriceps are commonly used to describe the dynamic stability of the knee. The conventional index is the most widely reported ratio in scientific literature, and it is estimated by dividing the maximum couple of the hamstring by the one of the quadriceps, on concentric/concentric form. A ratio of 0.6 at a speed of 60°/s, is considered to represent normal knee function. A strength imbalance greater than 10-15% of the bilateral index through an isokinetic test FR/ERCON60° could indicate that the rehabilitation program was unsuccessful, which prevents sportsmen to train and/or compete safely. For the professional football players, we can define as normal a value of 0.47 for the strength index FR/ERCON60°. In the literature, differences in isometric and isokinetic strength have been demonstrated between genders, with: women achieve 55.9% to 63.0% of the men's values.