Vol. 7, Issue 1, Part A (2025)

In tennis, the musculature of the lower extremities is subjected to high-intensity loads, sudden changes in direction, abrupt stops, and accelerations. Monitoring the physiological characteristics of tennis players' lower extremities can identify muscle imbalances and predispositions to injury, which can be addressed promptly through appropriate training programs. The aim of this study is to analyze the performance and time-based parameters obtained from isometric and isokinetic dynamometric measurements to provide a comprehensive evaluation of the physiological characteristics of junior tennis players. Methods Strength and time-based characteristics of the flexors and extensors of the knee joint were measured in two tennis players (A and B) at angular positions of 30°, 60°, 90°, and 100° and velocities of 60°/sec and 300°/sec, respectively, under isometric and concentric modes using an isokinetic dynamometer (Biodex 4 Pro, USA). Results The first tennis player exhibited weight, muscle mass, and fat mass above the optimal range for their age, while the second player was below the norm. The first player demonstrated very strong extensors with a short acceleration time. At 60°/sec, the non-dominant leg showed prolonged time to peak torque. This player displayed high work capacity and power during muscle contractions. The second tennis player generated slightly reduced peak torque values per kilogram of body weight. Acceleration time was within the normal range for both legs; however, the time to reach peak torque was prolonged. Conclusion Time-based and performance parameters enhance the comprehensive assessment of knee musculature in tennis players following dynamometric testing. Alongside strength characteristics, which provide key recommendations regarding knee joint musculature, these metrics indicate the presence of predispositions to non-contact knee injuries and the need for specialized training programs. Such programs should aim to maintain or improve components like work capacity, explosive strength, time parameters, agility, and other performance-related factors.