Characteristics of isometric muscle strength levels of bilateral knee joints in fighter pilots
Objective To analyze the characteristics of bilateral knee flexor and extensor muscle strength under different angular velocities in order to prevent knee injuries in fighter pilots.Methods Isokinetic plyometric tests were performed on 339 fighter pilots at three different angular velocities-60,180°/s and 300°/s.The peak torque of bilateral knee flexion and extension,the peak torque/body weight ratio,work fatigue,and the hamstring/quadriceps(H/Q)ratio were analyzed.Results At different angular velocities,there was statistically significant difference in the maximum muscle strength of bilateral knee joint flexion and extension(Fangular velocity=6 568.537,1 048.388,both P<0.001)and in the work fatigue of the flexor and extensor muscles of both knee joints(Fangular velocity=0.456,0.285,P<0.001,=0.593),especially between the dominant and non-dominant sides(Fbilateral=399.862,415.773,both P<0.001).The H/Q values of both knee joint flexion and extension were significant different at various angular velocities(Fangular velocity=6 216.789,P<0.001),and between the dominant and non-dominant sides(Fbilateral=13 813.530,P<0.001).Conclusion Bilateral knee extensor muscle strength of fighter pilots is higher than the average of sports population,but flexor muscle strength is generally lower.Fighter pilots should enhance hamstring muscle strength and quadriceps endurance to improve the balance of knee flexor and extensor muscle strength,thus improving knee stability and reducing knee training injuries.