Short-Burst Interval Treadmill Training Cerebral Palsy

Short-Burst Interval Treadmill Training to Improve Community Walking Activity and Mobility in Cerebral Palsy

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.

Participants are randomized to either short-burst interval locomotor treadmill training (SBLTT) or traditional locomotor treadmill training (TLTT)

SBLTT will consist of short-bursts (30 seconds) of high speed walking alternating with 30 seconds of low/moderate speed walking. Participant will receive 40 home-based sessions (5x/week for 8 weeks) of SBLTT

TLTT will consist of walking at steady-state speeds. Participant will receive 40 home-based sessions (5x/week for 8 weeks) of TLTT

SBLTT will consist of short-bursts (30 seconds) of high speed walking alternating with 30 seconds of low/moderate speed walking. Total duration of walking per session will be up to 30 minutes of the 30 second alternating intervals (30sec high / 30sec low/moderate) with rests as needed. Both groups will receive 40 sessions delivered 5x/week for 8 weeks. Initial speeds for high speed walking will be 75-80% of each participant's over ground baseline fast walking speed, and low/moderate speed will be 75-80% of self-selected speed calculated from the 10-Meter Walk Test.

TLTT group will receive the same number of sessions (40) delivered 5x/week for 8 weeks with a total duration of walking per session up to 30 minutes with rests as needed. TLTT will consist of walking at steady-state speeds. Initial treadmill speed will be 75-80% of over ground self-selected walking speed. The overall goal will be to achieve 30 minutes of walking at a steady-state walking speed within each session. Speed will be increased on the next session by .1 to .4mph when the subject can walk for 30 minutes on the treadmill at the current speed with an OMNI score of < 6/10.

StepWatch (SW) synchronized with Global Positioning System (GPS) - average strides per day in home versus community

StepWatch (SW) synchronized with Global Positioning System (GPS) - average strides per day low, medium or high stride rate in home versus community

Patient-Reported Outcomes Measurement Information System (PROMIS v1.0 Pediatric Profile) Mobility domain score

Inclusion Criteria: Bilateral 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