Muscle strengthening is not effective in children and adolescents with cerebral palsy: a systematic review

QuestionDo strengthening interventions increase strength without increasing spasticity and improve activity, and is there any carryover after cessation in children and adolescents with cerebral palsy?DesignSystematic review with meta-analysis of randomised trials.ParticipantsChildren with spastic cerebral palsy between school age and 20 years.InterventionStrengthening interventions that involved repetitive, strong, or effortful muscle contractions and progressed as ability changed, such as biofeedback, electrical stimulation, and progressive resistance exercise.Outcome measuresStrength was measured as continuous measures of maximum voluntary force or torque production. Spasticity was measured as velocity-dependent resistance to passive stretch. Activity was measured as continuous measures, eg, 10-m Walk Test, or using scales eg, the Gross Motor Function Measure.ResultsSix studies were identified and five had data that could be included in a metaanalysis. Strengthening interventions had no effect on strength (SMD 0.20, 95% CI −0.17 to 0.56), no effect on walking speed (MD 0.02 m/s, 95% CI −0.13 to 0.16), and had a small statistically-significant but not clinically-worthwhile effect on Gross Motor Function Measure (MD 2%, 95% CI 0 to 4). Only one study measured spasticity but did not report the between-group analysis.ConclusionIn children and adolescents with cerebral palsy who are walking, the current evidence suggests that strengthening interventions are neither effective nor worthwhile.