Feasibility and Potential Efficacy of High-Intensity Stepping Training in Variable Contexts in Subacute and Chronic Stroke

Abstract

Background Previous data suggest the amount and aerobic intensity of stepping training may improve walking post-stroke. Recent animal and human studies suggest training in challenging and variable contexts can also improve locomotor function. Such practice may elicit substantial stepping errors, although alterations in locomotor strategies to correct these errors could lead to improved walking ability. Objective This un-blinded, pretest-posttest pilot study was designed to evaluate the feasibility and preliminary efficacy of providing stepping practice in variable, challenging contexts (tasks and environments) at high aerobic intensities in participants with chronic (< 6 months) and subacute (1–6 months) stroke. Methods Twenty-five participants with stroke (gait speeds < 0.9 m/s with no more than moderate assistance) participated in ≤ 40 1-hr training sessions within 10 weeks. Stepping training in variable, challenging contexts was performed at 70–80% heart rate reserve, with feasibility measures of total steps/session, ability to achieve targeted intensities, patient tolerance, dropouts, and adverse events. Measures of daily stepping, gait speed, symmetry, and 6-min walk were performed every 4–5 weeks or 20 sessions with a 3 month follow-up. Results Twenty-two participants completed ≥ 4 weeks of training, averaging 2887±780 steps/session over 36±5.8 sessions. Self-selected and fastest speed, paretic single limb stance, and 6-min walk improved significantly at post-training and follow-up. Conclusions This preliminary study suggests stepping training at high aerobic intensity in variable contexts was tolerated by participants post-stroke, with significant locomotor improvements. Future trials should delineate the relative contributions of amount, intensity and variability of stepping training to maximize outcomes.

Effects of Dynamic Stepping Training on Nonlocomotor Tasks in Individuals Poststroke

“…The feasibility and preliminary efficacy of this intervention on locomotor outcomes have been described previously. 29 Here we describe changes in nonlocomotor tasks and impairments following this intervention.…”

Predictors of Functional Outcome Following Stroke

“…These associations suggest, as has recent clinical research, that highintensity gait training at aerobic levels of effort, focusing on walking speed, might improve timed gait distance and potentially facilitate return to community ambulation. 48 There has been limited research on predicting ambulation outcome with imaging. Lesion size and location have been associated with gait severity, but the level of injury to CST after stroke does not predict later walking speed or response to gait training.…”

Feasibility of Focused Stepping Practice During Inpatient Rehabilitation Poststroke and Potential Contributions to Mobility Outcomes

“…The amount of stepping activity was recorded per minute from 7:30 am to 5:00 pm on weekdays throughout the length of stay using validated accelerometers worn on the paretic ankle (StepWatch, Modus Health, LLC, Washington, DC) 21 ; such monitors are considered more accurate than other commercially available accelerometers, particularly at slower speeds. 22,23 The general intervention strategies to increase the amount of stepping practice at high aerobic intensities have been described previously 4,18 in patients >1 month poststroke with less severe physical impairments and performed outside of clinical therapy sessions. These interventions were discussed with the primary physical therapists treating the targeted patient population, and a multistrategy knowledge translation intervention was provided that included education and mentoring to improve adherence to the stepping program.…”