Effect of Reactive Balance Training on Physical Fitness Post-stroke

Reactive Balance Training and Fitness


Lead sponsor: Toronto Rehabilitation Institute

Collaborator: University of Toronto
Heart and Stroke Foundation of Canada

Source Toronto Rehabilitation Institute
Brief Summary

People with stroke should exercise to maintain function and reduce the risk of another stroke. Different types of exercise target different components of fitness, such as aerobic, strength, and balance. Post-stroke exercise guidelines exist for each type of exercise separately (eg, brisk walking as aerobic exercise, resistance training for strength, and Tai Chi for balance). Meeting these recommendations means spending a lot of time exercising, and people with stroke say that lack of time and fatigue are barriers to exercise. It is possible to target several components of fitness with one type of exercise.

'Reactive balance training' (RBT) is a type of exercise that improves control of reactions that are needed to prevent a fall after losing balance, and is the only type of exercise with potential to prevent falls in daily life post-stroke. Because RBT involves repeated whole-body movements it may have similar aerobic benefit as other exercises using whole-body movements (eg, brisk walking). Also, leg muscles need to generate a lot of force to make rapid steps in RBT; repeatedly generating this force may help to improve strength.

The purpose of this study is to determine if RBT improves two important components of fitness among people with chronic stroke: aerobic capacity and strength. The investigators expect that the improvements in aerobic capacity and strength after RBT will not be any worse than after an exercise program that specifically targets aerobic fitness and strength. A secondary purpose of this study is to determine the effects of RBT compared to aerobic and strength training on balance control and balance confidence. The investigators expect that RBT will lead to greater improvements in balance control and balance confidence than an aerobic and strength training program.

Detailed Description

This is an assessor-blind randomized non-inferiority trial with an internal pilot study. Research activities will take place at the Toronto Rehabilitation Institute and the University of Toronto. For the internal pilot study, we will initially recruit 20 participants with chronic stroke and randomly assign them to one of two groups: 1) RBT, or 2) AST. Cardiorespiratory fitness, lower-extremity strength, balance control, and balance confidence will be measured pre- and post-intervention. We will calculate the final target sample size using the variability observed in this internal pilot. Additionally, a Trial Steering Committee will determine the criteria for the progression from the internal pilot to the main study, and will decide on the continuation of the internal pilot with or without modifications based on those pre-defined criteria (e.g., criteria based on feasibility or preliminary evidence of effect of the interventions from examination of effect sizes).

Overall Status Recruiting
Start Date September 1, 2019
Completion Date August 2022
Primary Completion Date August 2021
Phase N/A
Study Type Interventional
Primary Outcome
Measure Time Frame
Aerobic capacity Data will be collected immediately pre- and post-intervention. We will analyse the change in the outcome from pre- to post-intervention.
Lower extremity strength Data will be collected immediately pre- and post-intervention. We will analyse the change in the outcome from pre- to post-intervention.
Secondary Outcome
Measure Time Frame
Berg balance scale Data will be collected immediately pre- and post-intervention. We will analyse the change in the outcome from pre- to post-intervention.
Mini-Balance Evaluation Systems Test Data will be collected immediately pre- and post-intervention. We will analyse the change in the outcome from pre- to post-intervention.
Six-minute walk test Data will be collected immediately pre- and post-intervention. We will analyse the change in the outcome from pre- to post-intervention.
Activities-specific Balance Confidence scale Data will be collected immediately pre- and post-intervention. We will analyse the change in the outcome from pre- to post-intervention.
Falls in daily life For 12 months post-intervention
Physical Activity Scale for Individuals with Physical Disabilities 4 months, 8 months, and 12 months post-intervention
Subjective Index of Physical and Social Outcome 4 months, 8 months, and 12 months post-intervention
Enrollment 70

Intervention type: Other

Intervention name: Reactive balance training

Description: A variety of tasks will be included to induce external or internal perturbations. External perturbations will be caused by forces outside participants' control (e.g. a push or pull from the physiotherapist). Internal perturbations are when the participant fails to control the centre of mass-base of support relationship during voluntary movement; e.g., 'agility' tasks such as kicking a soccer ball. Each session will include a five-minute warm-up, at least 60 perturbations, and a five-minute cool-down. The difficulty of the task will be set such that participants will 'fail' to recover balance ~50% of the time; 'failure' is defined as use of an upper extremity response, use of external assistance (i.e. from the overhead harness or physiotherapist), or taking more than 2 steps to regain stability. Training tasks will progressed by increasing the perturbation magnitude, including cognitive or movement tasks, or imposing sensory or environmental challenges (e.g. eyes closed, obstacles).

Arm group label: Reactive balance training

Intervention type: Other

Intervention name: Aerobic and strength training (AST)

Description: AST sessions will consist of 30 minutes of aerobic and 30 minutes of strength training. Aerobic training: Aerobic training will be done using treadmill walking or combination of modalities (e.g. cycling or recumbent stepping) for those unable to maintain the target heart rate with walking. The heart rate that occurred at the ventilatory threshold (V̇O2VT) during the cardiopulmonary exercise test will be used to prescribe intensity. In the absence of a discernible V̇O2VT a combination of the following will be used: 60-80% of heart rate reserve, peak oxygen uptake, and rating of perceived exertion of 11-16 (Borg 6-20 scale). Prescriptions will be initially progressed by increasing duration to ≥20 minutes and then increasing intensity to target heart rate. Resistance training: Participants will be prescribed 1-2 sets of 8 exercises per session (squat, heel raise, ankle dorsiflexion, knee extension and flexion, abdominal curl-up, wall push up, bicep curl), at 70% of 1 repetition maximum.

Arm group label: Aerobic and strength training



Inclusion Criteria:

- Community-dwelling adults with chronic stroke (>6 months post-stroke).

- Able to stand independently without upper-limb support for >30 seconds.

- Able to tolerate at least 10 postural perturbations while wearing a safety harness.

Exclusion Criteria:

- >2.1m tall and/or weighing >150kg (limits of the safety harness system).

- Other neurological condition that could affect balance control (e.g., Parkinson's disease).

- Lower extremity amputation.

- Cognitive, language or communication impairments affecting understanding instructions.

- Recent (last 6 months) significant illness, injury or surgery.

- Severe osteoporosis, defined by diagnosis of osteoporosis with fracture.

- Severe uncontrolled hypertension, or uncontrolled diabetes.

- Contraindications to exercise testing, such as symptomatic aortic stenosis, complex life-threatening arrhythmias, unstable angina, or orthostatic blood pressure decrease of >20 mmHg with symptoms.

- Acute or chronic illness or injury likely to be exacerbated by exercise (e.g., recent lower-extremity fracture).

- Currently attending in- or out-patient physiotherapy, in which they receive aerobic training, balance training or strength training for lower limb.

- Significant exercise participation: current physical activity levels that meet the recommended guidelines (at least 150 minutes of moderate-to-vigorous or at least 75 minutes of vigorous physical activity/week) as calculated using the moderate and vigorous components of the Leisure Time Exercise Questionnaire (LTEQ) in the month prior to starting the study.

- Received perturbation training at Toronto Rehab <1 year previously.

Gender: All

Minimum age: 18 Years

Maximum age: N/A

Healthy volunteers: No

Overall Official
Last Name Role Affiliation
Avril Mansfield, PhD Principal Investigator University Health Network, Toronto
Overall Contact

Last name: Avril Mansfield, PhD

Phone: 4165973422

Phone ext: 7831

Email: [email protected]

facility status contact Toronto Rehabilitation Institute Avril Mansfield, PhD 416-597-3422 7831 [email protected]
Location Countries


Verification Date

November 2019

Responsible Party

Responsible party type: Principal Investigator

Investigator affiliation: Toronto Rehabilitation Institute

Investigator full name: Avril Mansfield

Investigator title: Principal Investigator

Has Expanded Access No
Condition Browse
Number Of Arms 2
Arm Group

Arm group label: Reactive balance training

Arm group type: Experimental

Arm group label: Aerobic and strength training

Arm group type: Active Comparator

Patient Data No
Study Design Info

Allocation: Randomized

Intervention model: Parallel Assignment

Primary purpose: Treatment

Masking: Single (Outcomes Assessor)

Source: ClinicalTrials.gov