An electromyographic investigation of 4 elastic-tubing closed kinetic chain exercises after anterior cruciate ligament reconstruction

Autor: S S, Schulthies, M D, Ricard, K J, Alexander, J W, Myrer
Rok vydání: 2006
Předmět:
Zdroj: Journal of athletic training. 33(4)
ISSN: 1062-6050
Popis: To determine the electromyographic (EMG) activity of the vastus medialis oblique (VMO), vastus lateralis (VL), semitendinosus and semimembranosus (ST), and biceps femoris (BF) muscles during 4 elastic-tubing closed kinetic chain exercises in postoperative patients with anterior cruciate ligament (ACL)-reconstructed knees.A 4 x 4 repeated-measures analysis of variance design guided this study. Independent variables were type of exercise and muscle; the dependent variable was EMG activity.Fifteen patients, 5 to 24 weeks after ACL reconstruction.Subjects performed 4 exercises (front pull, back pull, crossover, reverse crossover) with elastic tubing attached to the foot of the uninjured leg. Time-and amplitude- normalized EMG activity was recorded from the VMO, VL, ST, and BF muscles of the injured leg. The hamstrings: quadriceps ratio was calculated.The normalized VMO, VL, and BF EMG activity ranged from 25% to 50% of maximum voluntary isometric contraction for the 4 exercises. The ST ranged from 12% on the back pull to 58% on the front pull. The hamstrings: quadriceps ratios were 137% (front pull), 115% (crossover), 70% (back pull), and 60% (reverse crossover).We suggest that clinicians use these exercises during early ACL rehabilitation since they incorporate early weightbearing with hamstring and quadriceps coactivation.
Databáze: OpenAIRE