Stroke often causes hemiparesis, affecting balance and walking ability. Propulsion, a major subtask of walking, has two components: trailing limb posture and propulsive force generated by plantarflexor muscles. Our group previously developed a method to challenge propulsion by accelerating the belt supporting the trailing limb during push off. In this study, we test the efficacy of a similar paradigm in 34 post-stroke individuals, and compare the effects of posterior belt accelerations applied to both legs (symmetric condition), and only to the paretic leg (asymmetric condition). We hypothesized that the two conditions would elicit changes in propulsion mechanics during and after exposure. Results indicate that belt accelerations induced measurable effects in paretic propulsion mechanics during exposure, and some of these effects persisted over a 1-3 minute post-exposure session conducted at self-selected speed. Specifically, by the end of the exposure session, participants increased their paretic TLA by $7.2~\pm~0.9$ %, and their plantarflexor muscle activation by $6.6 \pm 2.2$ % in the soleus and $7.8~\pm~2.3$ % in the lateral gastrocnemius, compared to their baseline. Changes in propulsion mechanics led to a small but statistically significant (0.024 m/s or $3.4 \pm 1.4$ %) post-exposure increase in self-selected walking speed. Effects were primarily induced on metrics of propulsion mechanics of the leg directly exposed to belt acceleration; therefore, differential effects as a function of acceleration condition were only observed for the non-paretic leg. A responder analysis indicated that individuals with greater impairment exhibited larger relative changes in plantarflexor muscle activation after exposure.

BACKGROUND:Strategic motor learning, guided by visual feedback (VF), is commonly used in post-stroke gait rehabilitation. While visuospatial working memory (VSWM) has been shown to support VF-guided motor correction in upper limb motor learning tasks, its role in locomotor learning after stroke remains unclear. OBJECTIVE:We examined whether VSWM is related to strategic learning by examining the overall accuracy and improvement in accuracy over time with VF-guided locomotor learning in individuals with chronic stroke. METHODS:Seventy-seven individuals >6 months post-stroke (41 males and 36 females; mean age = 66.3 ± 10.9 years) adapted walking on a split-belt treadmill (2:1 ratio) with real-time VF of step lengths. Feedback was displayed as visual targets on a screen and participants were instructed to use the visual cues to counteract the split-belt perturbation and restore their pre-perturbation step lengths. Strategic learning was assessed using 2 outcomes: overall accuracy and improvement in accuracy over strides during the VF phase. VSWM was assessed with the Spatial Addition subtest of the Wechsler Memory Scale-IV. RESULTS:After adjusting for age, sex, time since stroke, and lower extremity Fugl-Meyer score, VSWM explained a significant proportion of the variance in both outcomes (overall accuracy: ΔR2 = .085, P = .013; improvement in accuracy: ΔR2 = .153, P < .001). CONCLUSION:Our findings suggest that VSWM may be important for strategic locomotor learning with VF in people with chronic stroke, highlighting its potential relevance as a key consideration in designing walking rehabilitation strategies for people after stroke.

Objective To understand in people with stroke: (1) reasons for cardiopulmonary treadmill exercise test termination, (2) how frequently secondary criteria indicating a maximal test are met, and (3) how test termination is related to volume of oxygen consumption and participant characteristics. Design A secondary analysis from the Promoting Recovery Optimization of Walking Activity in Stroke (NCT02835313) clinical trial. Setting Four outpatient rehabilitation clinics. Participants People with chronic stroke able to walk without assistance of another person. Intervention Participants ( n = 250) randomized in a larger clinical trial completed symptom limited graded exercise treadmill tests pre- ( n = 247) and post-intervention ( n = 185). Treadmill exercise tests were conducted at constant speed with incremental incline increases. Main Measures The primary measure was reason for cardiopulmonary exercise test termination. Secondary measures included: oxygen consumption, ventilatory threshold, peak heart rate, respiratory exchange ratio, six-minute walk test, and fastest walking speed. Results There were six categories of test termination, electrocardiogram (11%), blood pressure/heart rate (13%), biomechanical (25%), self-selected (41%), equipment malfunction (8%), and other (2%). Only 1.9% of tests achieved the threshold to confirm a maximal aerobic effort. There were no differences in peak volume of oxygen consumption or participant characteristics between test termination categories. Conclusions Analyses indicate few with chronic stroke exhibit a maximal aerobic effort on a cardiopulmonary exercise test. If the cardiorespiratory system is not thoroughly taxed during treadmill exercise tests in people with chronic stroke, interpreting results as their cardiorespiratory fitness should be done cautiously.

BackgroundIndividuals with chronic stroke are less active, which is both a consequence of stroke-related impairments and a risk factor for future health complications. The PROWALKS clinical trial found significant gains in real-world walking activity (steps/day) after 12 weeks of a step activity monitoring behavioral intervention, provided either alone (SAM) or with high-intensity gait training (FAST + SAM), but not after high-intensity gait training alone (FAST). Previous research in individuals after stroke suggests that tailored behavioral counseling may lead to better long-term physical activity participation, but no previous work has focused on post-intervention maintenance of walking activity changes.ObjectiveTo investigate whether steps/day changes after training (POST) were maintained at 6 months (6MO) and 12 months (12MO) after baseline. We hypothesized that SAM and FAST + SAM groups would have better maintenance of steps/day changes than the FAST group. Methods. This analysis included all participants who completed the PROWALKS intervention (n = 200, mean[SD] age: 63.27[12.41], 102 male/98 female, >6 months post-stroke). Analysis outcomes were steps/day change from POST-6MO, and from POST-12MO.ResultsAll groups significantly decreased in steps/day from POST-6MO (P = .001, FAST decreased by mean[SE] 160[272], SAM by 1016[270], FAST + SAM by 400[300]), and POST-12MO (P < .001, FAST decreased by 610[280], SAM by 1072[306], FAST + SAM by 568[313]). There were no significant differences between groups.ConclusionsAll intervention groups showed significant declines in steps/day between POST and 6MO and between POST and 12MO. These results add to a growing body of literature suggesting that a behavioral intervention to initiate behavior change may not be sufficient for maintenance of change.Registration:This study is registered at ClinicalTrials.gov, NCT02835313.

BACKGROUND: Physical inactivity in people with chronic stroke profoundly affects daily function and increases recurrent stroke risk and mortality, making physical activity improvements an important target of intervention. We compared the effects of a high-intensity walking intervention (FAST), a step activity monitoring behavioral intervention (SAM), or a combined intervention (FAST+SAM) on physical activity (ie, steps/day). We hypothesized the combined intervention would yield the greatest increase in steps/day. METHODS: This assessor-blinded multisite randomized controlled trial was conducted at 4 university/hospital-based laboratories. Participants were 21 to 85 years old, walking without physical assistance following a single, unilateral noncerebellar stroke of ≥6 months duration, and randomly assigned to FAST, SAM, or FAST+SAM for 12 weeks (2–3 sessions/week). FAST training consisted of walking-related activities at 70% to 80% heart rate reserve, while SAM received daily feedback and goal setting of walking activity (steps/day). Assessors and study statistician were masked to group assignment. The a priori–determined primary outcome and end point was a comparison of the change in steps/day between the 3 intervention groups from pre- to post-intervention. Adverse events were tracked after randomization. All randomized participants were included in the intent-to-treat analysis. RESULTS: Participants were enrolled from July 18, 2016, to November 16, 2021. Of 2385 participants initially screened, 250 participants were randomized (mean [SE] age, 63 [0.80] years; 116 females/134 males), with 89 assigned to FAST, 81 to SAM, and 80 to FAST+SAM. Steps/day significantly increased in both the SAM (mean [SE], 1542 [267; 95% CI, 1014–2069] P <0.001) and FAST+SAM group (1307 [280; 95% CI, 752–1861] P <0.001) but not in the FAST group (406 [238; 95% CI, −63 to 876] P =0.09). There were no deaths or serious study-related adverse events. CONCLUSIONS: Only individuals with chronic stroke who completed a step activity monitoring behavioral intervention with skilled coaching and goal progression demonstrated improvements in physical activity (steps/day). REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02835313.

Peak oxygen consumption (VO2 peak), measured through cardiopulmonary exercise testing (CPET), is considered the gold standard to quantify a person’s cardiorespiratory fitness (CRF). CPET tests the multifaceted way in which the cardiorespiratory (CR), metabolic, musculoskeletal, and neurological systems interact to deliver and utilize oxygen during increased workloads. As studies of high intensity exercise in people with chronic stroke (PwS; > 6 months) have grown, CPET has been used to measure CRF in this population. PwS have VO2 peak values 53% of those found in age- and sex-matched controls, which likely plays a role in the presence of diminished mobility. Given significant neuromotor deficits experienced by PwS, peak performance may be impacted by neuromuscular factors. If the CR system is not the main limiting factor in CPET in PwS, the VO2 peak obtained may not accurately represent their CRF. PURPOSE: To characterize cardiorespiratory and metabolic responses to CPET in PwS. METHODS: PwS were included if their walking speed was 0.3-1.0 m/s and they walked <8000 steps/day. Participants underwent a maximal treadmill CPET with a 12-lead electrocardiogram and breath-by-breath analysis of oxygen consumption recording continuously. Treadmill speed was constant at 85% of the individual’s maximal treadmill speed. Participants first walked at 0% incline for 2 minutes, next at a 2% incline for 2 minutes, and then the incline increased by 2% each minute. Tests were terminated if biomechanical faults prevented participants from walking safely or per ACSM guidelines. RESULTS: 307 participants with chronic stroke (> 6 months; age (y) 63.1 + 12.7; 45.8% female, 40.6% on beta-blocker medication, BMI 30.5 + 6.3) completed a baseline CPET as part of a larger, multi-site randomized clinical trial (PROWALKS). Participants had an average resting VO2 of 2.7 + 0.96 mL/kg/min and VO2 peak of 11.8 + 5.2 mL/kg/min. Total exercise time was 4.9 + 2.7 minutes with a HRpeak of 125.8 + 21.4 beats/min (76% of age predicted HRmax) and RERpeak of 0.99 + 0.13. CPETs were ended for multiple reasons: a) self-selected stop (39.4%); b) clinician stopped due to BP or ECG (31.3%), or c) biomechanical faults (29.3%). CONCLUSION: Results suggest PwS rarely achieve ACSM criteria for a maximal test, indicating CPET results in PwS may not represent a true test of CRF.

Background Sedentary time is an independent construct from active time. Previous studies have examined variables associated with sedentary time to inform behavior change programs; however, these studies have lacked data sets that encompass potentially important domains. Objectives The purpose of this study was to build a more comprehensive model containing previously theorized important predictors of sedentary time and new predictors that have not been explored. We hypothesized that variables representing the domains of physical capacity, psychosocial, physical health, cognition, and environmental would be significantly related to sedentary time in individuals post-stroke. Methods This was a cross-sectional analysis of 280 individuals with chronic stroke. An activity monitor was used to measure sedentary (i.e. non-stepping) time. Five domains (8 predictors) were entered into a sequential linear regression model: physical capacity (6-Minute Walk Test, assistive device use), psychosocial (Activities Specific Balance Confidence Scale and Patient Health Questionnaire-9), physical health (Charlson Comorbidity Index and body mass index), cognition (Montreal Cognitive Assessment), and environmental (Area Deprivation Index). Results The 6-Minute Walk Test (beta = -0.39, p < .001), assistive device use (beta = 0.15, p = .03), Patient Health Questionnaire-9 (beta = 0.16, p = .01), and body mass index (beta = 0.11, p = .04) were significantly related to non-stepping time in individuals with chronic stroke. The model explained 28.5% of the variability in non-stepping time. Conclusions This work provides new perspective on which variables may need to be addressed in programs targeting sedentary time in stroke. Such programs should consider physical capacity, depressive symptoms, and physical health.

Supplemental Digital Content is Available in the Text. Background and Purpose: The transtheoretical model is a health behavior model used to understand an individual's readiness to change their behavior. This study aims to apply the transtheoretical model in understanding a person with stroke's readiness to change their activity level, as it relates to physical capacity, physical health, depressive symptoms, self-efficacy, and daily stepping activity. Methods: This was a cross-sectional analysis of baseline data from a clinical trial. Participants' readiness to change their activity levels was measured via self-report and daily stepping activity was measured using a step activity monitor. Robust regression (M-estimation with robust standard errors) was used to test the relationship between readiness to change and measures of physical capacity (6-minute walk test, self-selected walking speed), physical health (body mass index, age-adjusted Charlson Comorbidity Index), depressive symptoms (Patient Health Questionnaire-9), self-efficacy (Activities-Specific Balance Confidence Scale), and daily stepping (steps per day). Results: A total of 274 individuals were included in the analysis. Adjusted for age, readiness to change was positively related to daily stepping (β = 0.29, P < 0.001) and negatively related to depressive symptoms (β = −0.13, P = 0.01). Readiness to change was not significantly associated with measures of physical capacity, physical health, or self-efficacy. Discussion: These results suggest that individuals with stroke in the later stages of change may demonstrate greater daily stepping activity and lower depressive symptoms compared with those in earlier stages. Conclusions: Understanding the relationship between readiness to change, daily stepping, and depressive symptoms will help clinicians implement appropriate stage-specific intervention strategies and facilitate greater improvement in activity levels. Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A333).

Background: To assess the effects of the initial stepping limb on posterior fall recovery in individuals with chronic stroke, as well as to determine the benefits of fall-recovery training on these outcomes. Methods: This was a single-group intervention study of 13 individuals with chronic stroke. Participants performed up to six training sessions, each including progressively challenging, treadmill-induced perturbations from a standing position. Progressions focused on initial steps with the paretic or non-paretic limb. The highest perturbation level achieved, the proportion of successful recoveries, step and trunk kinematics, as well as stance limb muscle activation about the ankle were compared between the initial stepping limbs in the first session. Limb-specific outcomes were also compared between the first and last training sessions. Findings: In the first session, initial steps with the non-paretic limb were associated with a higher proportion of success and larger perturbations than steps with the paretic limb (p = 0.02, Cohen's d = 0.8). Paretic-limb steps were wider relative to the center of mass (CoM; p = 0.01, d = 1.3), likely due to an initial standing position with the CoM closer to the non-paretic limb (p = 0.01, d = 1.4). In the last training session, participants recovered from a higher proportion of perturbations and advanced to larger perturbations (p < 0.05, d > 0.6). There were no notable changes in kinematic or electromyography variables with training (p > 0.07, d < 0.5). Interpretation: The skill of posterior stepping in response to a perturbation can be improved with practice in those with chronic stroke, we were not able to identify consistent underlying kinematic mechanisms behind this adaptation.

Objective To identify homogeneous subsets of survivors of chronic stroke who share similar characteristics across several domains and test if these groups differ in real-world walking activity. We hypothesized that variables representing the domains of walking ability, psychosocial, environment, and cognition would be important contributors in differentiating real-world walking activity in survivors of chronic stroke. Design Cross-sectional, secondary data analysis. Setting University/laboratory. Participants A total of 283 individuals with chronic (≥6mo) stroke (N=238). Interventions Not applicable. Main Outcome Measures Thirteen variables representing 5 domains were included: (1) walking ability: 6-minute walk test (6MWT), self-selected speed (SSS) of gait; (2) psychosocial: Patient Health Questionnaire-9, Activities-specific Balance Confidence (ABC) scale; (3) physical health: low-density lipoprotein cholesterol, body mass index, Charlson Comorbidity Index (CCI); (4) cognition: Montreal Cognitive Assessment (MoCA); and (5) environment: living situation and marital status, work status, Area Deprivation Index (ADI), Walk Score. Mixture modeling was used to identify latent classes of survivors of stroke. After identifying the latent classes, walking activity, measured as steps per day (SPD), was included as a distal outcome to understand if classes were meaningfully different in their real-world walking Results A model with 3 latent classes was selected. The 6MWT, SSS, ABC scale, and Walk Score were significantly different among all 3 classes. Differences were also seen for the MoCA, ADI, and CCI between 2 of the 3 classes. Importantly, the distal outcome of SPD was significantly different in all classes, indicating that real-world walking activity differs among the groups identified by the mixture model. Conclusions Survivors of stroke with lower walking ability, lower self-efficacy, lower cognitive abilities, and greater area deprivation had lower SPD. These results demonstrate that the physical and social environment (including socioeconomic factors) and cognitive function should also be considered when developing interventions to improve real-world walking activity after stroke.

Background: Stroke survivors are more sedentary than the general public. Previous research on stroke activity focuses on linear quantities. Non-linear measures, such as Jensen-Shannon Divergence and Lempel-Ziv Complexity, may help explain when and how stroke survivors move so that interventions to increase activity may be designed more effectively.Objectives: Our objective was to understand what factors affect a stroke survivor's physical activity, including weather, by characterizing activity by step counts, structure, and complexity.Methods: A custom MATLAB code was used to analyze clinical trial (NCT02835313, https://clinicaltrials.gov/ct2/show/NCT02835313) data presented as minute by minute step counts. Six days of data were analyzed for 142 participants to determine the regularity of activity structure across days and complexity patterns of varied cadences. The effect of steps on structure and complexity, the season's effect on steps, structure, and complexity, and the presence of precipitation's effect on steps and complexity were all analyzed.Results: Step counts and regularity were linearly related (p < 0.001). Steps and complexity were quadratically related (r2 = 0.70 for mean values, 0.64 for daily values). Season affected complexity between spring and winter (p = 0. 019). Season had no effect on steps or structure. Precipitation had no effect on steps or complexity.Conclusions: Stroke survivors with high step counts are active at similar times each day and have higher activity complexities as measured through patterns of movement at different intensity levels. Non-linear measures, such as Jensen-Shannon Divergence and Lempel-Ziv Complexity, are valuable in describing a person's activity. Weather affects our activity parameters in terms of complexity between spring and winter.

Exercise has failed to reduce falls in those with chronic stroke. A limitation of traditional exercise is that the motor responses needed to prevent a fall are not elicited (i.e. they lack processing specificity). Balance reactions often require compensatory steps. Therefore, interventions that target such steps have the potential to reduce falls. Computerized treadmills can deliver precise, repeatable, and challenging perturbations as part of a training protocol. The objective of this study was to develop and determine the feasibility of such training applied to those with chronic stroke. We developed the training to address specificity, appropriate duration and repetition, and progressive overloading and individualization. We hypothesized that our intervention would be acceptable, practical, safe, and demonstrate initial signs of efficacy. In this single-arm study, thirteen individuals with chronic stroke (29–77 years old, 2–15 years post stroke) performed up to six training sessions using a computer-controlled treadmill. Each session had separate progressions focused on initial steps with the non-paretic or paretic limbs in response to anterior or posterior falls. Perturbation magnitudes were altered based on performance and tolerance. Acceptability was determined by adherence, or the number of sessions completed. Practicality was documented by the equipment, space, time, and personnel. Adverse events were documented to reflect safety. In order to determine the potential-efficacy of this training, we compared the proportion of successful recoveries and the highest perturbation magnitude achieved on the first and last sessions. The training was acceptable, as evident by 12/13 participants completing all 6 sessions. The protocol was practical, requiring one administrator, the treadmill, and a harness. The protocol was safe, as evident by no serious or unanticipated adverse events. The protocol demonstrated promising signs of efficacy. From the first to last sessions, participants had a higher proportion of successful recoveries and progressed to larger disturbances. Using a computerized treadmill, we developed an approach to fall-recovery training in individuals with chronic stroke that was specific, considered duration and repetition, and incorporated progressive overloading and individualization. We demonstrated that this training was acceptable, practical, safe, and potentially beneficial for high-functioning individuals with chronic stroke. Retrospectively registered at clinicaltrials.gov ( NCT03638089 ) August 20, 2018.

Stroke survivors are more physically inactive than even the most sedentary older adults, and low activity is associated with increased risk of recurrent stroke, medical complications, and mortality. We hypothesize that the combination of a fast walking intervention that improves walking capacity, with a step activity monitoring program that facilitates translation of gains from the clinic to the “real-world”, would generate greater improvements in real world walking activity than with either intervention alone.

BackgroundRecent research demonstrated that the symmetry of corticomotor drive with the paretic and nonparetic plantarflexor muscles was related to the biomechanical ankle moment strategy that people with chronic stroke used to achieve their greatest walking speeds. Rehabilitation strategies that promote corticomotor balance might improve poststroke walking mechanics and enhance functional ambulation.ObjectiveThe study objectives were to test the effectiveness of a single session of gait training using functional electrical stimulation (FES) to improve plantarflexor corticomotor symmetry and plantarflexion ankle moment symmetry and to determine whether changes in corticomotor symmetry were related to changes in ankle moment symmetry within the session.DesignThis was a repeated-measures crossover study.MethodsOn separate days, 20 people with chronic stroke completed a session of treadmill walking either with or without the use of FES of their ankle dorsi- and plantarflexor muscles. We calculated plantarflexor corticomotor symmetry using transcranial magnetic stimulation and plantarflexion ankle moment symmetry during walking between the paretic and the nonparetic limbs before and after each session. We compared changes and tested relationships between corticomotor symmetry and ankle moment symmetry following each session.ResultsFollowing the session with FES, there was an increase in plantarflexor corticomotor symmetry that was related to the observed increase in ankle moment symmetry. In contrast, following the session without FES, there were no changes in corticomotor symmetry or ankle moment symmetry.LimitationsNo stratification was made on the basis of lesion size, location, or clinical severity.ConclusionsThese findings demonstrate, for the first time (to our knowledge), the ability of a single session of gait training with FES to induce positive corticomotor plasticity in people in the chronic stage of stroke recovery. They also provide insight into the neurophysiologic mechanisms underlying improvements in biomechanical walking function.

Background/Purpose: Many factors appear to be related to physical activity after stroke, yet it is unclear how these factors interact and which ones might be the best predictors. Therefore, the purpose of this study was twofold: (1) to examine the relationship between walking capacity and walking activity, and (2) to investigate how biopsychosocial factors and self-efficacy relate to walking activity, above and beyond walking capacity impairment poststroke. Methods: Individuals greater than 3 months poststroke (n = 55) completed the Yesavage Geriatric Depression Scale (GDS), Fatigue Severity Scale (FSS), Modified Cumulative Illness Rating (MCIR) Scale, Walk 12, Activities-Specific Balance Confidence (ABC) Scale, Functional Gait Assessment (FGA), and oxygen consumption testing. Walking activity data were collected via a StepWatch Activity Monitor. Predictors were grouped into 3 constructs: (1) walking capacity: oxygen consumption and FGA; (2) biopsychosocial: GDS, FSS, and MCIR; (3) self-efficacy: Walk 12 and ABC. Moderated sequential regression models were used to examine what factors best predicted walking activity. Results: Walking capacity explained 35.9% (P < 0.001) of the variance in walking activity. Self-efficacy (ΔR 2 = 0.15, P < 0.001) and the interaction between the FGA×ABC (ΔR 2 = 0.047, P < 0.001) significantly increased the variability explained. The FGA (β = 0.37, P = 0.01), MCIR (β = -0.26, P = 0.01), and Walk 12 (β = −0.45, P = 0.00) were each individually significantly associated with walking activity. Discussion and Conclusion: Although measures of walking capacity and self-efficacy significantly contributed to “real-world” walking activity, balance self-efficacy moderated the relationship between walking capacity and walking activity. Improving balance self-efficacy may augment walking capacity and translate to improved walking activity poststroke. Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A139).

BACKGROUND:Walking dysfunctions persist following poststroke rehabilitation. A major limitation of current rehabilitation efforts is the inability to identify modifiable deficits that, when improved, will result in the recovery of walking function. Previous studies have relied on cross-sectional analyses to identify deficits to target during walking rehabilitation; however, these studies did not account for the influence of a key covariate - maximum walking speed. OBJECTIVE:To determine the relationships between commonly studied poststroke variables and the long-distance walking function of individuals poststroke when controlling for maximum walking speed. METHODS:Correlation analyses of cross-sectional data from 57 individuals more than 6 months poststroke measured the relationships between standing balance, walking balance, balance self-efficacy, lower extremity motor function, and maximum walking speed versus long-distance walking function. For a subgroup of subjects who completed training, the relationship between changes in maximum walking speed versus changes in long-distance walking function was assessed. RESULTS:Each measurement of interest strongly correlated with long-distance walking function (rs from 0.448 to 0.900, all Ps ≤ .001); however, when controlling for maximum walking speed, none of the other measurements remained related to long-distance walking function. In contrast, when controlling for each of the other measurements, maximum walking speed remained highly related. Moreover, changes in maximum walking speed resulting from training were highly related to changes in long-distance walking function (r = .737, P ≤ .001). CONCLUSIONS:For individuals in the chronic phase of stroke recovery, improving maximum walking speed may be necessary to improve long-distance walking function.