The effect of quadriceps femoris muscle strengthening exercises on spasticity in children with cerebral palsy.

BACKGROUND AND PURPOSE: The Bobath neurodevelopmental treatment approach advised against the use of resistive exercise, as proponents felt that increased effort would increase spasticity. The purpose of this study was to test the premise that the performance of exercises with maximum efforts will increase spasticity in people with cerebral palsy (CP). Spasticity, in the present study, was defined as a velocity-dependent hyperexcitability of the muscle stretch reflex. SUBJECTS: Twenty-four subjects with the spastic diplegic form of CP (mean age=11.4 years, SD=3.0, range=7-17) and 12 subjects without known neurological impairments (mean age=11.6 years, SD=3.5, range=7-17) were assessed. METHODS: Knee muscle spasticity was assessed bilaterally using the pendulum test to elicit a stretch reflex immediately before and after 3 different forms of right quadriceps femoris muscle exercise (isometric, isotonic, and isokinetic) during a single bout of exercise training. Pendulum test outcome measures were: (1) first swing excursion, (2) number of lower leg oscillations, and (3) duration of the oscillations. RESULTS: There were no changes in spasticity following exercise between the 2 groups of subjects. DISCUSSION AND CONCLUSION: These results do not support the premise that exercises with maximum efforts increase spasticity in people with CP.