Ballistic strength training in adults with cerebral palsy may increase rate of force development in plantar flexors, but transition to walking remains unclear: a case series.

BACKGROUND: Persons with cerebral palsy (CP) walk with reduced ankle plantar flexor power compared to typically developing. In this study, we investigated whether a ballistic strength-training programme targeting ankle plantar flexors could improve muscle strength, muscle architecture and walking function in adults with CP. METHODS: Eight adults (mildly affected CP) underwent eight weeks of ballistic strength training, with two sessions per week. Before and after the intervention preferred walking speed, ankle plantar flexion rate of force development (RFD), maximal voluntary contraction (MVC), muscle thickness, pennation angle and fascicle length were measured. Data are presented for individuals, as well as for groups. Group changes were analysed using the Wilcoxon signed-rank test. RESULTS: Data were analysed for eight participants (five women, mean age 37.9 years; six GMFCS I and two GMFCS II). Two participants increased their walking speed, but there were no significant group changes. In terms of muscle strength, there were significant group changes for RFD at 100 ms and MVC. In the case of muscle architecture, there were no group changes. CONCLUSION: In this study, we found that eight weeks of ballistic strength training improved ankle plantar flexor muscle strength but walking function and muscle architecture were unchanged. Larger studies will be needed to obtain conclusive evidence of the efficacy of this training method.

Can adults with cerebral palsy perform and benefit from ballistic strength training to improve walking outcomes? A mixed methods feasibility study.

BACKGROUND: Power bursts of hips and ankle plantar flexors are prerequisites to walking propulsion. However, these power bursts are reduced during gait for persons with cerebral palsy (CP) and mainly in the ankle plantar flexors. Hence, task specific training, such as ballistic strength training, is suggested to increase muscle power in walking but not investigated in adults with CP. Therefore, the aim was to investigate if adults with CP could perform and benefit from ballistic strength training to improve walking, evaluated through physical measures and self-reported measures and interviews. METHODS: In this mixed methods feasibility study, eight ambulatory adults (aged 24-56) with spastic CP conducted ballistic strength training on a glideboard targeting the ankle plantarflexors two times a week for eight weeks. The feasibility of the training was assessed through objectives described by Orsmond and Cohn. Before and after the intervention, physical measures (6-Minute Walk Test and the eight-item High-level Mobility Assessment Tool) and self-reported measures (Patient Global Impression of Change, Numeric Pain Rating Scale, Fatigue Impact and Severity Self-Assessment, and Walk-12) were collected. After the intervention, semi-structured interviews explored experiences of this training. RESULTS: The participants experienced training the ankle plantar flexor as relevant but reported it took about four weeks to coordinate the exercises successfully. Although we observed no changes in the physical performance measures, most participants reported improvements; some felt steadier when standing, walking, and hopping. CONCLUSION: This study demonstrated that ballistic strength training was feasible and suitable in adults with CP. However, guidance and a long (4 weeks) familiarization time were reported necessary to master the exercises. Most participants reported self-experienced improvements, although no physical performance measures improved. Thus, prolonged intervention may be required for perceived physical improvements to emerge. Also, other outcome measures sensitive to power output remains to be investigated.

Walking through life with cerebral palsy: reflections on daily walking by adults with cerebral palsy.

Purpose: Walking is a major target in childhood physiotherapy for children with cerebral palsy (CP). Little information exists on the importance or value of walking when these children grow up. The aim of this study was to explore personal reflections on daily walking by adults with CP.Method: Semi-structured individual interviews were conducted and analysed with systematic text condensation, a four-step thematic cross-case analysis.Results: Eight ambulatory adults (26-60 years, four women and four men) with CP were interviewed. Almost all had experienced deteriorated walking ability in adulthood and reported that walking was restricted and affected by intrinsic features, such as pain, fatigue, reduced balance and fear of falling. Extrinsic features such as being looked at due to walking abnormality and environmental factors, such as seasonal changes affected their free walking and was common. Some had accepted using mobility aids for energy conservation.Conclusions: Both intrinsic and extrinsic factors influence walking in adults with CP. Reflections by the adults with CP suggest these features may reduce participation in public spaces and potentially increase acceptance and use of mobility aids.

The impact of motor task and environmental constraints on gait patterns during treadmill walking in a fully immersive virtual environment.

BACKGROUND: Virtual environments (VE) are increasingly used in rehabilitation settings for gait training, and positive effects are reported. However, little is known about how walking under environmental constraints and solving motor tasks in fully immersive VEs impact gait patterns. RESEARCH QUESTION: How are gait patterns in healthy adults impacted by walking under environmental constraints and solving motor tasks on a treadmill, in a fully immersive VE? METHODS: 29 healthy adults (age: 28.9±4.8 yrs) were included. Basic gait parameters (step length, cadence, walk ratio) and gait variability in the anteroposterior, mediolateral and vertical directions were measured using an inertial sensor attached to the lower back. A familiarisation treadmill walk >2 min was performed, followed by 200 m familiarisation walk in the VE with no task or environmental constraints The participants were then exposed to height, two grabbing tasks, a balancing task and narrow-path walking. Gait patterns were captured for 15-25 seconds during each of the conditions. The Simulator Sickness Questionnaire was completed before and after the session. RESULTS: Gait regularity decreased when solving all the motor tasks, and under all the environmental constraints, except when being familiarised to height exposure, where regularity returned to pre-exposure levels. Step length and walk ratio decreased, and cadence increased during height exposure and while performing the grabbing tasks and the balancing task. The different tasks and environments appeared to have specific impact on gait patterns. There was no increase in simulator sickness symptoms. SIGNIFICANCE: Gait patterns were impacted by solving motor tasks, and by environmental constraints, in healthy young adults, suggesting increased need for balance control. We suggest that VE-training on a treadmill holds potential for improving gait and balance control.