Effect of Individualized High-Velocity (Power) Resistance Training on Gait Biomechanics of Children with Cerebral Palsy

Abstract

High-velocity resistance (HVRT) training can increase gait speed and reduce power asymmetries in adults; but this intervention is seldom provided to younger persons, particularly those with chronic disease states such as cerebral palsy (CP). PURPOSE: To determine if HVRT targeting the specific needs of each patient could improve gait patterns in children with CP. METHODS: Five subjects (1 male, 4 females, age 12.8 ± 4.3 yrs., height 1.4 ± .01 m, weight 37.9 ± 15.8 kg) participated in a 12-week HVRT program. During session 1, each subject’s gait pattern was recorded via a three-dimensional wireless inertial gait analysis system (YEI Technology, USA). Also their one repetition maximums were determined for the leg press, hip abduction, chest press, and seated row on pneumatic resistance machines (Keiser Corp, Fresno, CA). During session 2, children’s optimal loads for power were determined to establish their training loads. Based on their results tailored unilateral and bilateral programs were provided for each child. Loads were then adjusted using power plateaus throughout the training period. RESULTS: Subject 1 increased knee flexion in the pre-swing phase for her right knee and improved maximum knee flexion for the left knee during the swing phase. While right hip extension was limited by an undersized assistive devise; her left hip ROM improved substantially. Subject 2 increased propulsion and knee flexion ROM during the swing phase and increased left and right knee ROM during the stance phase. Hip ROM did not improve perhaps due to tight hip flexors resulting from a constantly flexed position when using an assistive device. Subject 3 showed improvement in the right knee but not the left. Improvements in the hip were seen as reduced hyperextension and increased extension for the right and left sides, respectively. Subject 4 showed an increase in right knee flexion in the swing phase with no change for the left knee and improved ROM for both hips, though only the right attained a neutral position in the transition phase. Subject 5 showed improved ROM in both knees and the left and right hips showed increased hip extension in the stance phase. CONCLUSIONS: These results show the potential for targeted HVRT to improve gait in CP children as evidenced by curves that more closely follow the typical patterns seen in children without CP.