EFFECTS OF QUADRICEPS FEMORIS MUSCLE STRENGTHENING ON CROUCH GAIT IN CHILDREN WITH SPASTIC DIPLEGIA

Background and Purpose. Despite evidence of weakness in children with cerebral palsy, the use of strength training in this population remain s controversial. Subjects. Fourteen children with spastic diplegia, ra nging in age from 6 to 14 years ((X) over bar=9.1, SD= 2.5), participa ted in a bilateral quadriceps femoris muscle strengthening program. Me thods. The children exercised three times per week for 6 weeks using a nkle weights at loads of approximately 65% of each child's maximum iso tonic force production. The maximal voluntary contraction of the quadr iceps femoris muscles was measured before, at the mid-point of and imm ediately following the exercise program at 30, 60, and 90 degrees of k nee flexion. Gait analyses were performed before and after the strengt hening program to determine whether quadriceps femoris muscle strength ening influenced gait. Results. Children with spastic diplegia can inc rease quadriceps femoris muscle strength through heavy resistance exer cise. Repeated-measures analysis of variance and multivariate analysis of variance procedures were used to assess changes in force and in ga it variables. Improvement in the degree of crouch at initial floor con tact at the freely selected speed and an increase in stride length at free and fast speeds were found, Conclusion and Discussion. These find ings suggest that resistance exercise is an effective treatment strate gy and as such should be considered as one component in the habilitati on of children with cerebral palsy.