Comparison of Isokinetic Muscle Strength and Torque Development Speed of the Knee Joint in Middle-Aged Adults by Gender

The present study aims to investigate gender-specific characteristics of strength expression by comparing isokinetic knee strength and the rate of torque development (RTD) in middle-aged men and women. The participants included 10 middle-aged men and 11 women who had not engaged in moderate-to-vigorous physical activity for the past six months. Each participant performed five repetitions of knee extension at an angular velocity of 60°/s, during which segmental torque and RTD were measured. The results revealed significant temporal differences in segmental isokinetic torque. In the male group, a marked increase was observed at 50ms, 100ms, and 200ms, whereas the female group exhibited a gradual increase after 50ms. The segmental RTD demonstrated a significant interaction effect between group and time, with a notable increase observed in the 250-300ms interval in the male group. In conclusion, the findings highlight clear gender differences in strength expression among middle-aged adults, suggesting that hypertrophy-based resistance training is essential to enhance late-phase strength development in middle-aged women.