Effects of Preoperative Isokinetic Eccentric Training and Whey Protein Isolate Supplement on Quadriceps Strength and Knee Function in Patients with Anterior Cruciate Ligament Rupture / 中国医学科学院学报

ABSTRACT

Objective To explore the effect of preoperative isokinetic eccentric training with or not whey protein isolate supplement before operation on lower limb muscle strength and knee function in patients with anterior cruciate ligament (ACL) rupture. Methods A total of 22 male volunteers aged 18-40 years with ACL rupture were recruited in outpatient service. With randomized block design,subjects were randomly assigned to isokinetic eccentric training (IE) group and isokinetic eccentric training with whey protein isolate supplement (IE+WPI) group. The IE group received isokinetic eccentric training of the injured limb on an isokinetic dynamometer under the guidance of physiatrist in laboratory before operation. There were 3-4 sets per day with 8-10 repetitions for each set,twice a week,with at least one day between sessions. The IE+WPI group were supplied with whey protein isolate 22 g per day on the basis of isokinetic eccentric training,taking breakfast or 30-60 minutes after the training. The intervention lasted for 6 weeks. Isokinetic muscle strength of limbs,the function and laxity of knee,the circumferences of thigh and knee,and the body composition were measured before and after the treatment. Results Compared with baseline,the peak torque (PT) of isokinetic-eccentric contraction (IE group41.0%,P=0.018;IE+WPI group46.7%,P=0.008) and the concentric contraction (IE group29.6%,P=0.018;IE+WPI group38.9%,P=0.038) of quadriceps in the two training groups significantly increased after isokinetic eccentric training. The Lysholm score increased significantly in IE+WPI group compared with baseline (P=0.018). Conclusions Isokinetic eccentric training before operation for ACL rupture patients can increase the strength of quadriceps and improve the function of knees. Protein isolate supplement can improve such effect.