Quadriceps function and training after knee ligament surgery.

A follow-up study of 30 patients operated on for knee ligament injuries was performed with measurements of maximal isometric and isokinetic (angular velocity 30, 42, 120 degrees/s) torque for knee extension and muscle biopsy from vastus laternalis. The maximal torque values of the operated side were reduced in spite of resumed physical activities and athletic training. Isokinetic training, weight training (10 RM), and self-training were compared. All training groups increased their muscle strength with the largest increase for the isokinetically trained group. Before training, the mean fiber areas were somewhat low, especially for type II fibers and there was a tendency for an increase after training. There was no significant change in ATP, CP, and contractile enzyme activities with training. With the isokinetic training principle, maximal torque can in contrast to weight training be achieved through the whole range of motion, which may explain its larger training effect.