Effects of Weight Resistance on the Temporal Parameters and Electromyography of Sit-to-Stand Movements in Children With and Without Cerebral Palsy

Abstract

The purpose of this study was to examine the differences in phase durations and electromyography between children with and without cerebral palsy during sit-to-stand movements with weight resistance. Fifteen children with cerebral palsy and 15 age-matched children with typical development were recruited. They performed sit-to-stand movements while wearing a vest with four different loads (none, low, moderate, and high). Three phases during sit-to-stand and electromyography of vastus lateralis, gluteus maximus, and medial hamstring were recorded. The ascending phase and peak electromyography of vastus lateralis showed a significant interaction between groups and resistance conditions. The children with cerebral palsy took a longer time to stand up than the control group when the load was high (P = 0.004). The peak electromyography of vastus lateralis increased with increasing resistance in the control group (P < 0.017) but not in children with cerebral palsy. Children with cerebral palsy had a higher cocontraction ratio of the medial hamstring/vastus lateralis than the control group (P = 0.001) at all resistance levels. Children with cerebral palsy took a longer time for the task but did not increase agonist contraction as the control group in response to higher loads. Future research is suggested to see whether agonist contraction will be improved with strengthening therapy.