Ambulatory children with cerebral palsy (CP) walk predominately in low intensity stride rates with little variability, thus limiting their walking activity and ability to participate in daily life. In contrast, typically developing (TD) children engage in short bursts of intense walking activity interspersed with varying intervals of low intensity walking within daily life. In order to optimize motor learning, active participation, task-specific training and multiple repetitions or massed practice is required to learn new motor skills. Short bursts of vigorous intensity locomotor treadmill training (SBLTT) alternating with low/moderate intensity was specifically designed to mimic activity patterns of TD children in a massed practice format. Pilot data suggests that SBLTT is feasible and enhances walking capacity and performance in daily life for children with CP. This project will examine the effect of SBLTT versus an equivalent dosage of traditional locomotor treadmill training (TLTT) on the primary outcomes of walking capacity and performance in children with CP and whether the effects of SBLTT on walking capacity and performance are mediated by improvements in in muscle power generation. The scientific premise is that SBLTT, that approximates the walking intensity patterns of typically developing (TD) children through a home-based massed practice protocol, will be more effective than TLTT in improving walking capacity and performance. We hypothesize that SBLTT strategies for children with CP modeled on walking patterns of TD children, will be positively mediated by muscle power generation and subsequently improve walking capacity and community walking performance and mobility. Specific aims. Aim #1. Determine the immediate and retention effects of short-burst interval LTT (SBLTT) on walking capacity in ambulatory children with CP. Aim #2. Examine the effects of treatment on community-based walking activity performance and mobility. Aim #3. Explore whether the effects of SBLTT on walking capacity and performance are mediated by muscle power generation. The proposed research will be the first step in a continuum of research that is expected to direct locomotor training protocols and rehab strategies across pediatric disabilities and positively effecting the community walking performance and mobility for children with CP.

In a randomized clinical trial, 72 ambulatory children with spastic CP (6-10 yrs.) will receive either SBLTT or an equivalent dosage of TLTT for 40 sessions, 5x/week for 8 weeks in a massed practice format. The only difference between training protocols will be the variable training (interval fast versus steady state walking speeds). Thus, the key ingredient will be the intensity of the interval training delivered in a serial blocked practice schedule. Outcomes will be collected at baseline, 4 and 8 weeks to assess dosage, and 24 weeks post training for long term retention with the primary endpoint at 8 weeks.

Inclusion Criteria:

• Bilateral and unilateral spastic cerebral palsy
• Gross Motor Function Classification Levels II & III
• Ages 6 years to < 11 years

Exclusion Criteria:

• Orthopedic or neurosurgery < 9 months prior
• Injection therapy (Botulinum Toxin/Phenol) < 3 months prior