Impact of loaded sit-to-stand exercises at different speeds on the physiological cost of walking in children with spastic diplegia: A single-blind randomized clinical trial

•We determined whether different speeds loaded sit-to-stand exercises improved the physiological cost of walking.•This design was a single-blind randomized clinical trial.•Children with cerebral palsy (CP) were randomly allocated to different speeds loaded sit-to-stand exercise groups.•6-min walk distance and the Physiological Cost Index improved after intervention in the slow sit-to-stand exercise group.•Slow low loaded STS exercise could improve the physiologic cost of walking in children with CP. In the present study, we aimed to determine whether similarly loaded sit-to-stand exercises at different speeds improve the physiological cost of walking in children with spastic diplegia. This design was a single-blind randomized clinical trial. Sixteen children with cerebral palsy (CP), aged 12–18 years, with a diagnosis of spastic diplegia, were randomly allocated to a slow loaded sit-to-stand exercise group (n=8) and a self-paced loaded sit-to-stand exercise group (n=8). Loaded sit-to-stand exercise was conducted at home for 15min, 4 sets per day, 3–4days per week, for 6 weeks. The patients were evaluated immediately before the intervention and after the training. Lower limb muscle strength using a hand-held dynamometer, selective voluntary motor control using SCALE, 6-min walk distance (6MWD), and Physiological Cost Index (PCI) were measured. The 6MWD showed a significant difference before and after intervention. PCI showed a significant difference between the two groups and the two time points. 6MWD and the PCI improved after intervention in the slow sit-to-stand exercise group. Compared to loaded sit-to-stand exercise at a regular speed, slow low-loaded sit-to-stand exercise improved the 6MWD and PCI in children with CP, suggesting that this decrease in speed during exercise improves the physiological cost of walking in these children.