Multimodal Exercise Training Poststroke

Summary

Individuals poststroke with gait and balance impairment are typically less active and have low levels of physical fitness. Improving fitness level while also improving gait and balance is very important. Maximizing the exercise training benefit requires the appropriate level of effort is achieved. Traditional exercise programs scale aerobic demand by increasing the walking speed or the slope of the treadmill surface. This may be difficult for individuals who experience decreased balance at faster speeds or on sloped surfaces and require the use of handrails to safely walk under these conditions. These exercise programs show limited improvement in walking ability after training. This project will test a novel approach, resistance-based treadmill walking, for maximizing improvements in fitness and ability to walk by individuals poststroke. The investigators previous research has shown that backward directed resistive force applied to the pelvis while walking is well tolerated by individuals poststroke. Further, these forces can be used to effectively scale aerobic demand while walking in a controlled manner. With traditional treadmill training approaches handrail support is utilized to ensure safety. However, handrail support externally stabilizes the individual reducing training improvements in walking capacity and balance. For this pilot investigation a group that aerobically trains using a standard exercise treadmill training paradigm will be compared to a group that experiences progressive backward directed resistive forces applied to an individuals' pelvis while they walk at comfortable walking speeds without the aid of handrails. Individuals will wear a fall harness that provides no external stabilization but prevents falls to the treadmill surface. This approach has the potential benefit of allowing individuals poststroke to meaningfully practice walking at safe speeds but against resistance thereby improving walking economy, dynamic balance, and walking speed. The proposed project is necessary to gather preliminary data for a much larger training study that has the potential to change the clinical approach for improving gait economy, balance, and walking speed for individuals poststroke.

Conditions

• Exercise
• Stroke

Interventions

OTHER

Resistance Based Training

Resistance based training study: Each training session will begin by determining the treadmill walking speed that an individual will train. The speed of the treadmill will be incrementally increased stepwise and individuals will affirm which speed feels the most comfortable to walk. Thus, the training speed of individuals will not necessarily be fixed over the 8-week study. Heart rate will be monitored and resistive force will be applied stepwise until the heart rate reaches at least 60% heart rate reserve. Individuals will be encouraged to walk at least five minutes and then allowed to rest. Achieved heart rate reserve and time the spent training at 60-80% heart rate reserve will be quantified for each session. Subjective measures of effort will also be sampled using the Borg Scale.

OTHER

Speed Based Training

Speed based training study: Individuals will train at the fastest walking speed that an individual asserts that they can maintain for five minutes. The training time will then begin. Individuals will be encouraged to walk at least five minutes and then be allowed to rest. Speed will be progressed for each individual every 1-2 weeks at increments between 0.02 m/s and 0.08 m/s. Treadmill inclination will remain at 0°. Participants will be allowed to use the handrail or forearm support while being encouraged to walk without support if possible. Achieved heart rate reserve and the time the spent training at 60-80% heart rate reserve will be quantified for each session. Subjective measures of effort will also be sampled using the Borg Scale.

Sponsors & Collaborators

• National Institutes of Health (NIH)

  collaborator NIH

• University of Alabama at Birmingham

  lead OTHER

Principal Investigators

• Christopher P Hurt, PhD · University of Alabama at Birmingham

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

75 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2017-07-01

Primary Completion

2018-06-30

Completion

2020-06-30

Countries

• United States

Study Locations