Task-Oriented Aerobic Exercise in Chronic Hemiparetic Stroke: Training Protocols and Treatment Effects

Effect of High-Intensity Interval Training and Moderate-Intensity Continuous Training in People With Poststroke Gait Dysfunction: A Randomized Clinical Trial

Background The exercise strategy that yields the greatest improvement in both cardiorespiratory fitness (V ̇ O 2 peak $$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$ ) and walking capacity poststroke has not been determined. This study aimed to determine whether conventional moderate-intensity continuous training (MICT) or high-intensity interval training (HIIT) have different effects on V ̇ O 2 peak $$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$ and 6-minute walk distance (6MWD). Methods and Results In this 24-week superiority trial, people with poststroke gait dysfunction were randomized to MICT (5 days/week) or HIIT (3 days/week with 2 days/week of MICT). MICT trained to target intensity at the ventilatory anaerobic threshold. HIIT trained at the maximal tolerable treadmill speed/grade using a novel program of 2 work-to-recovery protocols: 30:60 and 120:180 seconds. V̇O2 and heart rate was measured during performance of the exercise that was prescribed at 8 and 24 weeks for treatment fidelity. Main outcomes were change in V ̇ O 2 peak $$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$ and 6MWD. Assessors were blinded to the treatment group for V ̇ O 2 peak $$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$ but not 6MWD. Secondary outcomes were change in ventilatory anaerobic threshold, cognition, gait-economy, 10-meter gait-velocity, balance, stair-climb performance, strength, and quality-of-life. Among 47 participants randomized to either MICT (n=23) or HIIT (n=24) (mean age, 62±11 years; 81% men), 96% completed training. In intention-to-treat analysis, change in V ̇ O 2 peak $$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$ for MICT versus HIIT was 2.4±2.7 versus 5.7±3.1 mL·kg-1·min-1 (mean difference, 3.2 [95% CI, 1.5-4.8]; P<0.001), and change in 6MWD was 70.9±44.3 versus 83.4±53.6 m (mean difference, 12.5 [95% CI, -17 to 42]; P=0.401). HIIT had greater improvement in ventilatory anaerobic threshold (mean difference, 2.07 mL·kg-1·min-1 [95% CI, 0.59-3.6]; P=0.008). No other between-group differences were observed. During V̇O2 monitoring at 8 and 24 weeks, MICT reached 84±14% to 87±18% of V ̇ O 2 peak $$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$ while HIIT reached 101±22% to 112±14% of V ̇ O 2 peak $$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$ (during peak bouts). Conclusions HIIT resulted in more than a 2-fold greater and clinically important change in V ̇ O 2 peak $$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$ than MICT. Training to target (ventilatory anaerobic threshold) during MICT resulted in ~3 times the minimal clinically important difference in 6MWD, which was similar to HIIT. These findings show proof of concept that HIIT yields greater improvements in cardiorespiratory fitness than conventional MICT in appropriately screened individuals. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03006731.

Optimal Intensity and Duration of Walking Rehabilitation in Patients With Chronic Stroke: A Randomized Clinical Trial

Importance

For walking rehabilitation after stroke, training intensity and duration are critical dosing parameters that lack optimization.

Objective

To assess the optimal training intensity (vigorous vs moderate) and minimum training duration (4, 8, or 12 weeks) needed to maximize immediate improvement in walking capacity in patients with chronic stroke.

Design, Setting, and Participants

This multicenter randomized clinical trial using an intent-to-treat analysis was conducted from January 2019 to April 2022 at rehabilitation and exercise research laboratories. Survivors of a single stroke who were aged 40 to 80 years and had persistent walking limitations 6 months or more after the stroke were enrolled.

Interventions

Participants were randomized 1:1 to high-intensity interval training (HIIT) or moderate-intensity aerobic training (MAT), each involving 45 minutes of walking practice 3 times per week for 12 weeks. The HIIT protocol used repeated 30-second bursts of walking at maximum safe speed, alternated with 30- to 60-second rest periods, targeting a mean aerobic intensity above 60% of the heart rate reserve (HRR). The MAT protocol used continuous walking with speed adjusted to maintain an initial target of 40% of the HRR, progressing up to 60% of the HRR as tolerated.

Main Outcomes and Measures

The main outcome was 6-minute walk test distance. Outcomes were assessed by blinded raters after 4, 8, and 12 weeks of training.

Results

Of 55 participants (mean [SD] age, 63 [10] years; 36 male [65.5%]), 27 were randomized to HIIT and 28 to MAT. The mean (SD) time since stroke was 2.5 (1.3) years, and mean (SD) 6-minute walk test distance at baseline was 239 (132) m. Participants attended 1675 of 1980 planned treatment visits (84.6%) and 197 of 220 planned testing visits (89.5%). No serious adverse events related to study procedures occurred. Groups had similar 6-minute walk test distance changes after 4 weeks (HIIT, 27 m [95% CI, 6-48 m]; MAT, 12 m [95% CI, -9 to 33 m]; mean difference, 15 m [95% CI, -13 to 42 m]; P = .28), but HIIT elicited greater gains after 8 weeks (58 m [95% CI, 39-76 m] vs 29 m [95% CI, 9-48 m]; mean difference, 29 m [95% CI, 5-54 m]; P = .02) and 12 weeks (71 m [95% CI, 49-94 m] vs 27 m [95% CI, 3-50 m]; mean difference, 44 m [95% CI, 14-74 m]; P = .005) of training; HIIT also showed greater improvements than MAT on some secondary measures of gait speed and fatigue.

Conclusions and Relevance

These findings show proof of concept that vigorous training intensity is a critical dosing parameter for walking rehabilitation. In patients with chronic stroke, vigorous walking exercise produced significant and meaningful gains in walking capacity with only 4 weeks of training, but at least 12 weeks were needed to maximize immediate gains.

Trial Registration

ClinicalTrials.gov Identifier: NCT03760016.

Training parameters and longitudinal adaptations that most strongly mediate walking capacity gains from high-intensity interval training post-stroke

Background

Locomotor high-intensity interval training (HIIT) has been shown to improve walking capacity more than moderate-intensity aerobic training (MAT) after stroke, but it is unclear which training parameter(s) should be prioritized (e.g. speed, heart rate, blood lactate, step count) and to what extent walking capacity gains are the result of neuromotor versus cardiorespiratory adaptations.

Objective

Assess which training parameters and longitudinal adaptations most strongly mediate 6-minute walk distance (6MWD) gains from post-stroke HIIT.

Methods

The HIT-Stroke Trial randomized 55 persons with chronic stroke and persistent walking limitations to HIIT or MAT and collected detailed training data. Blinded outcomes included 6MWD, plus measures of neuromotor gait function (e.g. fastest 10-meter gait speed) and aerobic capacity (e.g. ventilatory threshold). This ancillary analysis used structural equation models to compare mediating effects of different training parameters and longitudinal adaptations on 6MWD.

Results

Net gains in 6MWD from HIIT versus MAT were primarily mediated by faster training speeds and longitudinal adaptations in neuromotor gait function. Training step count was also positively associated with 6MWD gains, but was lower with HIIT versus MAT, which decreased the net 6MWD gain. HIIT generated higher training heart rate and lactate than MAT, but aerobic capacity gains were similar between groups, and 6MWD changes were not associated with training heart rate, training lactate, or aerobic adaptations.

Conclusions

To increase walking capacity with post-stroke HIIT, training speed and step count appear to be the most important parameters to prioritize.

Impact of Constraint-Induced Movement Therapy (CIMT) on Functional Ambulation in Stroke Patients-A Systematic Review and Meta-Analysis

Constraint-induced movement therapy (CIMT) has been delivered in the stroke population to improve lower-extremity functions. However, its efficacy on prime components of functional ambulation, such as gait speed, balance, and cardiovascular outcomes, is ambiguous. The present review aims to delineate the effect of various lower-extremity CIMT (LECIMT) protocols on gait speed, balance, and cardiovascular outcomes. Material and methods: The databases used to collect relevant articles were EBSCO, PubMed, PEDro, Science Direct, Scopus, MEDLINE, CINAHL, and Web of Science. For this analysis, clinical trials involving stroke populations in different stages of recovery, >18 years old, and treated with LECIMT were considered. Only ten studies were included in this review, as they fulfilled the inclusion criteria. The effect of CIMT on gait speed and balance outcomes was accomplished using a random or fixed-effect model. CIMT, when compared to controlled interventions, showed superior or similar effects. The effect of LECIMT on gait speed and balance were non-significant, with mean differences (SMDs) of 0.13 and 4.94 and at 95% confidence intervals (Cis) of (-0.18-0.44) and (-2.48-12.37), respectively. In this meta-analysis, we observed that despite the fact that several trials claimed the efficacy of LECIMT in improving lower-extremity functions, gait speed and balance did not demonstrate a significant effect size favoring LECIMT. Therefore, CIMT treatment protocols should consider the patient's functional requirements, cardinal principles of CIMT, and cardiorespiratory parameters.

Effect of Pulmonary Function Training with a Respirator on Functional Recovery and Quality of Life of Patients with Stroke

A stroke is a sudden onset cerebral blood circulation disorder. It occurs in patients with cerebrovascular disease due to various predisposing factors causing stenosis, occlusion, or rupture of intracerebral arteries, which, in turn, causes acute cerebral blood circulation disturbance and clinically manifests as symptoms and signs of excessive or permanent cerebral dysfunction. It can cause serious harm to patients' physical and mental health. This study aimed to evaluate the effect of Breathe-Link breathing trainers on lung function and the ability to perform activities of daily living in patients with stroke. Sixty patients with stroke were randomly divided into two groups. One group was set as the control group and received routine breathing training. The experimental group received a Breathe-Link trainer based on regular training, with rehabilitation training for 12 weeks as the time node. Respiratory muscle strength, respiratory velocity, respiratory capacity, forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), and rate in the first second (FEV1/FVC) were used to evaluate the respiratory function of patients, and the Barthel index was used to evaluate the ability to perform activities of daily living. Improvements in respiratory function and daily living ability were compared between the two groups. After 12 weeks of training, respiratory muscle strength, respiratory velocity, respiratory volume, FVC, FEV1, FEV1/FVC, and Barthel index of patients in the two groups improved compared with those before training (P < 0.05), and the improvement in the treatment group was better than that in the control group (P < 0.05). Breathe-Link breathing trainers can improve lung function and the ability to perform activities of daily living in patients with stroke, and its effect is acceptable. It can be recommended for clinical use.

Rehabilitation of Upper Limb Motor Impairment in Stroke: A Narrative Review on the Prevalence, Risk Factors, and Economic Statistics of Stroke and State of the Art Therapies

Stroke has been one of the leading causes of disability worldwide and is still a social health issue. Keeping in view the importance of physical rehabilitation of stroke patients, an analytical review has been compiled in which different therapies have been reviewed for their effectiveness, such as functional electric stimulation (FES), noninvasive brain stimulation (NIBS) including transcranial direct current stimulation (t-DCS) and transcranial magnetic stimulation (t-MS), invasive epidural cortical stimulation, virtual reality (VR) rehabilitation, task-oriented therapy, robot-assisted training, tele rehabilitation, and cerebral plasticity for the rehabilitation of upper extremity motor impairment. New therapeutic rehabilitation techniques are also being investigated, such as VR. This literature review mainly focuses on the randomized controlled studies, reviews, and statistical meta-analyses associated with motor rehabilitation after stroke. Moreover, with the increasing prevalence rate and the adverse socio-economic consequences of stroke, a statistical analysis covering its economic factors such as treatment, medication and post-stroke care services, and risk factors (modifiable and non-modifiable) have also been discussed. This review suggests that if the prevalence rate of the disease remains persistent, a considerable increase in the stroke population is expected by 2025, causing a substantial economic burden on society, as the survival rate of stroke is high compared to other diseases. Compared to all the other therapies, VR has now emerged as the modern approach towards rehabilitation motor activity of impaired limbs. A range of randomized controlled studies and experimental trials were reviewed to analyse the effectiveness of VR as a rehabilitative treatment with considerable satisfactory results. However, more clinical controlled trials are required to establish a strong evidence base for VR to be widely accepted as a preferred rehabilitation therapy for stroke.

Backward Locomotor Treadmill Training Differentially Improves Walking Performance across Stroke Walking Impairment Levels

Background: Post-stroke walking impairment is a significant cause of chronic disability worldwide and often leads to loss of life roles for survivors and their caregivers. Walking impairment is traditionally classified into mild (>0.8 m/s), moderate (0.41–0.8 m/s), and severe (≤0.4 m/s), and those categorized as “severe” are more likely to be homebound and at greater risk of falls, fractures, and rehospitalization. In addition, there are minimal effective walking rehabilitation strategies currently available for this subgroup. Backward locomotor treadmill training (BLTT) is a novel and promising training approach that has been demonstrated to be safe and feasible across all levels of impairment; however, its benefits across baseline walking impairment levels (severe (≤0.4 m/s) vs. mild–moderate (>0.4 m/s)) have not been examined. Methods: Thirty-nine adults (>6 months post-stroke) underwent 6 days of BLTT (3×/week) over 2 weeks. Baseline and PRE to POST changes were measured during treadmill training and overground walking. Results: Individuals with baseline severe walking impairment were at a more significant functional disadvantage across all spatiotemporal walking measures at baseline and demonstrated fewer overall gains post-training. However, contrary to our working hypothesis, both groups experienced comparable increases in cadence, bilateral percent single support times, and step lengths. Conclusion: BLTT is well tolerated and beneficial across all walking impairment levels, and baseline walking speed (≤0.4 m/s) should serve as a covariate in the design of future walking rehabilitation trials.

Muscle Oxygenation of the Paretic and Nonparetic Legs During and After Arterial Occlusion in Chronic Stroke

Oxygen delivery and demand are reduced in the paretic leg post-stroke, reflecting decreased vascular function and reduced muscle quantity and quality. However, it is unknown how muscle oxygenation, the balance between muscle oxygen delivery and utilization, is altered in chronic stroke during and after occlusion-induced ischemia.

OBJECTIVES

The objective was to determine muscle oxygen consumption rate, microvascular responsiveness and reactive hyperemia in the paretic and nonparetic legs during and after arterial occlusion post-stroke.

MATERIALS AND METHODS

Muscle oxygen saturation was measured with near-infrared spectroscopy on the vastus lateralis of each leg during 3-minute arterial occlusion and recovery (3 min). Muscle oxygen consumption was derived from the desaturation slope during ischemia, microvascular responsiveness was derived from the resaturation slope after ischemia and reactive hyperemia was derived from the area under the curve above baseline after ischemia.

RESULTS

Eleven subjects (91% male; 32.2±6.1 months post-stroke; age 62.9±13.6 years) with a hemiparetic gait pattern participated. There was no significant between-leg muscle oxygenation difference at rest (paretic: 64.9±16.6%; nonparetic: 70.6±15.6%, p = 0.13). Muscle oxygen consumption in the paretic leg (-0.53±0.24%/s) was significantly reduced compared to the nonparetic leg (-0.70±0.36%/s; p = 0.03). Microvascular responsiveness was significantly reduced in the paretic leg compared to the nonparetic leg (paretic: 4.6±1.8%/s; nonparetic: 5.7±1.6%/s, p = 0.04). Reactive hyperemia was not significantly different between legs (paretic:4384±2341%·s; nonparetic: 3040±2216%·s, p = 0.07).

CONCLUSION

Muscle oxygen consumption and microvascular responsiveness are impaired in the paretic compared to the nonparetic leg, suggesting both reduced skeletal muscle aerobic function and reduced ability to maximally perfuse muscle tissue.

Aerobic Exercise After Left-Sided Stroke Improves Gait Speed and Endurance: A Prospective Cohort Study

OBJECTIVE

The aim of the study was to investigate the effects of aerobic exercise on individuals who have had a stroke and showed baseline scores lower than the standard scores for the 6-min and 10-meter walk tests.

DESIGN

Individuals were assigned to groups according to gait performance, defined by the standard values in the 6-min and 10-meter walk tests (standard baseline score and lower baseline score), and brain injury side. Aerobic exercise, 30 mins per day, 2 times a week, for a total of 12 wks. The 6-min and 10-meter walk tests in five assessments: initial, after 4, 8, 12 wks, and 4 wks of follow-up, analyzed by multivariate analysis, with P value of less than 0.05.

RESULTS

The 6-min walk test data showed an increase in endurance for lower baseline score and left-brain injury, during assessments 4, and follow-up, compared with standard baseline score (F4,84 = 14.64). Lower baseline score showed endurance increase for assessments 2, 3, 4, and follow-up compared with assessment 1 (F4,84 = 7.70). The 10-meter walk test data showed an increase in speed for lower baseline score and left-brain injury, during assessments 3, 4, and follow-up, compared with assessment 1, 4, and follow-up, compared with assessment 2 (F4,84 = 5.33).

CONCLUSIONS

Aerobic exercise increases gait endurance and speed in individuals who have had a stroke, with left-brain injury, and lower baseline score in the 6-min and 10-meter walk tests.

Clinical Practice Guideline to Improve Locomotor Function Following Chronic Stroke, Incomplete Spinal Cord Injury, and Brain Injury

BACKGROUND

Individuals with acute-onset central nervous system (CNS) injury, including stroke, motor incomplete spinal cord injury, or traumatic brain injury, often experience lasting locomotor deficits, as quantified by decreases in gait speed and distance walked over a specific duration (timed distance). The goal of the present clinical practice guideline was to delineate the relative efficacy of various interventions to improve walking speed and timed distance in ambulatory individuals greater than 6 months following these specific diagnoses.

METHODS

A systematic review of the literature published between 1995 and 2016 was performed in 4 databases for randomized controlled clinical trials focused on these specific patient populations, at least 6 months postinjury and with specific outcomes of walking speed and timed distance. For all studies, specific parameters of training interventions including frequency, intensity, time, and type were detailed as possible. Recommendations were determined on the basis of the strength of the evidence and the potential harm, risks, or costs of providing a specific training paradigm, particularly when another intervention may be available and can provide greater benefit.

RESULTS

Strong evidence indicates that clinicians should offer walking training at moderate to high intensities or virtual reality-based training to ambulatory individuals greater than 6 months following acute-onset CNS injury to improve walking speed or distance. In contrast, weak evidence suggests that strength training, circuit (ie, combined) training or cycling training at moderate to high intensities, and virtual reality-based balance training may improve walking speed and distance in these patient groups. Finally, strong evidence suggests that body weight-supported treadmill training, robotic-assisted training, or sitting/standing balance training without virtual reality should not be performed to improve walking speed or distance in ambulatory individuals greater than 6 months following acute-onset CNS injury to improve walking speed or distance.

DISCUSSION

The collective findings suggest that large amounts of task-specific (ie, locomotor) practice may be critical for improvements in walking function, although only at higher cardiovascular intensities or with augmented feedback to increase patient's engagement. Lower-intensity walking interventions or impairment-based training strategies demonstrated equivocal or limited efficacy.

LIMITATIONS

As walking speed and distance were primary outcomes, the research participants included in the studies walked without substantial physical assistance. This guideline may not apply to patients with limited ambulatory function, where provision of walking training may require substantial physical assistance.

SUMMARY

The guideline suggests that task-specific walking training should be performed to improve walking speed and distance in those with acute-onset CNS injury although only at higher intensities or with augmented feedback. Future studies should clarify the potential utility of specific training parameters that lead to improved walking speed and distance in these populations in both chronic and subacute stages following injury.

DISCLAIMER

These recommendations are intended as a guide for clinicians to optimize rehabilitation outcomes for persons with chronic stroke, incomplete spinal cord injury, and traumatic brain injury to improve walking speed and distance.

A randomized controlled trial of motor imagery combined with structured progressive circuit class therapy on gait in stroke survivors

Structured Progressive Circuit Class Therapy (SPCCT) was developed based on task-oriented therapy, providing benefits to patients’ motivation and motor function. Training with Motor Imagery (MI) alone can improve gait performance in stroke survivors, but a greater effect may be observed when combined with SPCCT. Health education (HE) is a basic component of stroke rehabilitation and can reduce depression and emotional distress. Thus, this study aimed to investigate the effect of MI with SPCCT against HE with SPCCT on gait in stroke survivors. Two hundred and ninety stroke survivors from 3 hospitals in Yangon, Myanmar enrolled in the study. Of these, 40 stroke survivors who passed the selection criteria were randomized into an experimental (n = 20) or control (n = 20) group. The experimental group received MI training whereas the control group received HE for 25 minutes prior to having the same 65 minutes SPCCT program, with both groups receiving training 3 times a week over 4 weeks. Temporo-spatial gait variables and lower limb muscle strength of the affected side were assessed at baseline, 2 weeks, and 4 weeks after intervention. After 4 weeks of training, the experimental group showed greater improvement than the control group in all temporospatial gait variables, except for the unaffected step length and step time symmetry which showed no difference. In addition, greater improvements of the affected hip flexor and knee extensor muscle strength were found in the experimental group. In conclusion, a combination of MI with SPCCT provided a greater therapeutic effect on gait and lower limb muscle strengths in stroke survivors.

Backward locomotor treadmill training combined with transcutaneous spinal direct current stimulation in stroke: a randomized pilot feasibility and safety study

Walking impairment impacts nearly 66% of stroke survivors and is a rising cause of morbidity worldwide. Despite conventional post-stroke rehabilitative care, the majority of stroke survivors experience continued limitations in their walking speed, temporospatial dynamics and walking capacity. Hence, novel and comprehensive approaches are needed to improve the trajectory of walking recovery in stroke survivors. Herein, we test the safety, feasibility and preliminary efficacy of two approaches for post-stroke walking recovery: backward locomotor treadmill training and transcutaneous spinal direct current stimulation. In this double-blinded study, 30 chronic stroke survivors (>6 months post-stroke) with mild-severe residual walking impairment underwent six 30-min sessions (three sessions/week) of backward locomotor treadmill training, with concurrent anodal (N = 19) or sham transcutaneous spinal direct current stimulation (N = 11) over the thoracolumbar spine, in a 2:1 stratified randomized fashion. The primary outcomes were: per cent participant completion, safety and tolerability of these two approaches. In addition, we collected data on training-related changes in overground walking speed, cadence, stride length (baseline, daily, 24-h post-intervention, 2 weeks post-intervention) and walking capacity (baseline, 24-h post-intervention, 2 weeks post-intervention), as secondary exploratory aims testing the preliminary efficacy of these interventions. Eighty-seven per cent (N = 26) of randomized participants completed the study protocol. The majority of the study attrition involved participants with severe baseline walking impairment. There were no serious adverse events in either the backward locomotor treadmill training or transcutaneous spinal direct current stimulation approaches. Also, both groups experienced a clinically meaningful improvement in walking speed immediately post-intervention that persisted at the 2-week follow-up. However, in contrast to our working hypothesis, anodal-transcutaneous spinal direct current stimulation did not enhance the degree of improvement in walking speed and capacity, relative to backward locomotor treadmill training + sham, in our sample. Backward locomotor treadmill training and transcutaneous spinal direct current stimulation are safe and feasible approaches for walking recovery in chronic stroke survivors. Definitive efficacy studies are needed to validate our findings on backward locomotor treadmill training-related changes in walking performance. The results raise interesting questions about mechanisms of locomotor learning in stroke, and well-powered transcutaneous spinal direct current stimulation dosing studies are needed to understand better its potential role as a neuromodulatory adjunct for walking rehabilitation.

Effects of Exercise Intensity on Acute Circulating Molecular Responses Poststroke

Background. Exercise intensity can influence functional recovery after stroke, but the mechanisms remain poorly understood. Objective. In chronic stroke, an intensity-dependent increase in circulating brain-derived neurotrophic factor (BDNF) was previously found during vigorous exercise. Using the same serum samples, this study tested acute effects of exercise intensity on other circulating molecules related to neuroplasticity, including vascular-endothelial growth factor (VEGF), insulin-like growth factor-1 (IGF1), and cortisol, with some updated analyses involving BDNF. Methods. Using a repeated-measures design, 16 participants with chronic stroke performed 3 exercise protocols in random order: treadmill high-intensity interval training (HIT-treadmill), seated-stepper HIT (HIT-stepper), and treadmill moderate-intensity continuous exercise (MCT-treadmill). Serum molecular changes were compared between protocols. Mediation and effect modification analyses were also performed. Results. VEGF significantly increased during HIT-treadmill, IGF1 increased during both HIT protocols and cortisol nonsignificantly decreased during each protocol. VEGF response was significantly greater for HIT-treadmill versus MCT-treadmill when controlling for baseline. Blood lactate positively mediated the effect of HIT on BDNF and cortisol. Peak treadmill speed positively mediated effects on BDNF and VEGF. Participants with comfortable gait speed ≥0.4 m/s had significantly lower VEGF and higher IGF1 responses, with a lower cortisol response during MCT-treadmill. Conclusions. BDNF and VEGF are promising serum molecules to include in future studies testing intensity-dependent mechanisms of exercise on neurologic recovery. Fast training speed and anaerobic intensity appear to be critical ingredients for eliciting these molecular responses. Serum molecular response differences between gait speed subgroups provide a possible biologic basis for previously observed differences in training responsiveness.

Adaptive Physical Activity for Stroke: An Early-Stage Randomized Controlled Trial in the United States

Background. As stroke survival improves, there is an increasing need for effective, low-cost programs to reduce deconditioning and improve mobility. Objective. To conduct a phase II trial examining whether the community-based Italian Adaptive Physical Activity exercise program for stroke survivors (APA-Stroke) is safe, effective, and feasible in the United States. Methods. In this single-blind, randomized controlled trial, 76 stroke survivors with mild to moderate hemiparesis >6 months were randomized to either APA-Stroke (N = 43) or Sittercise (N = 33). APA-Stroke is a progressive group exercise regimen tailored to hemiparesis that includes walking, strength, and balance training. Sittercise, a seated, nonprogressive aerobic upper body general exercise program, served as the control. Both interventions were 1 hour, 3 times weekly, in 5 community locations, supervised by exercise instructors. Results. A total of 76 participants aged 63.9 ± 1.2 years, mean months poststroke 61.8 ± 9.3, were included. There were no serious adverse events; completion rates were 58% for APA-Stroke, 70% for Sittercise. APA-Stroke participants improved significantly in walking speed. Sample size was inadequate to demonstrate significant between-group differences. Financial and logistical feasibility of the program has been demonstrated. Ongoing APA classes have been offered to >200 participants in county Senior Centers since study completion. Conclusion. APA-Stroke shows great promise as a low-cost, feasible intervention. It significantly increased walking speed. Safety and feasibility in the US context are demonstrated. A pivotal clinical trial is required to determine whether APA-Stroke should be considered standard of care.

Exercise intensity affects acute neurotrophic and neurophysiological responses poststroke

Aerobic exercise may acutely prime the brain to be more responsive to rehabilitation, thus facilitating neurologic recovery from conditions like stroke. This aerobic priming effect could occur through multiple mechanisms, including upregulation of circulating brain-derived neurotrophic factor (BDNF), increased corticospinal excitability, and decreased intracortical inhibition. However, optimal exercise parameters for targeting these mechanisms are poorly understood. This study tested the effects of exercise intensity on acute BDNF and neurophysiological responses. Sixteen ambulatory persons >6 mo poststroke performed three different 20-min exercise protocols in random order, approximately 1 wk apart, including the following: 1) treadmill high-intensity interval training (HIT-treadmill); 2) seated-stepper HIT (HIT-stepper); and 3) treadmill moderate-intensity continuous exercise (MCT-treadmill). Serum BDNF and transcranial magnetic stimulation measures of paretic lower limb excitability and inhibition were assessed at multiple time points during each session. Compared with MCT-treadmill, HIT-treadmill elicited significantly greater acute increases in circulating BDNF and corticospinal excitability. HIT-stepper initially showed BDNF responses similar to HIT-treadmill but was no longer significantly different from MCT-treadmill after decreasing the intensity in reaction to two hypotensive events. Additional regression analyses showed that an intensity sufficient to accumulate blood lactate appeared to be important for eliciting BDNF responses, that the interval training approach may have facilitated the corticospinal excitability increases, and that the circulating BDNF response was (negatively) related to intracortical inhibition. These findings further elucidate neurologic mechanisms of aerobic exercise and inform selection of optimal exercise-dosing parameters for enhancing acute neurologic effects. NEW & NOTEWORTHY Acute exercise-related increases in circulating BDNF and corticospinal excitability are thought to prime the brain for learning. Our data suggest that these responses can be obtained among persons with stroke using short-interval treadmill high-intensity interval training, that a vigorous aerobic intensity sufficient to generate lactate accumulation is needed to increase BDNF, that interval training facilitates increases in paretic quadriceps corticospinal excitability, and that greater BDNF response is associated with lesser intracortical inhibition response.

A Challenge-Based Approach to Body Weight-Supported Treadmill Training Poststroke: Protocol for a Randomized Controlled Trial

Background

Body weight support treadmill training protocols in conjunction with other modalities are commonly used to improve poststroke balance and walking function. However, typical body weight support paradigms tend to use consistently stable balance conditions, often with handrail support and or manual assistance.

Objective

In this paper, we describe our study protocol, which involved 2 unique body weight support treadmill training paradigms of similar training intensity that integrated dynamic balance challenges to help improve ambulatory function post stroke. The first paradigm emphasized walking without any handrails or manual assistance, that is, hands-free walking, and served as the control group, whereas the second paradigm incorporated practicing 9 essential challenging mobility skills, akin to environmental barriers encountered during community ambulation along with hands-free walking (ie hands-free + challenge walking).

Methods

We recruited individuals with chronic poststroke hemiparesis and randomized them to either group. Participants trained for 6 weeks on a self-driven, robotic treadmill interface that provided body weight support and a safe gait-training environment. We assessed participants at pre-, mid- and post 6 weeks of intervention-training, with a 6-month follow-up. We hypothesized greater walking improvements in the hands-free + challenge walking group following training because of increased practice opportunity of essential mobility skills along with hands-free walking.

Results

We assessed 77 individuals with chronic hemiparesis, and enrolled and randomized 30 individuals poststroke for our study (hands-free group=19 and hands-free + challenge walking group=20) from June 2012 to January 2015. Data collection along with 6-month follow-up continued until January 2016. Our primary outcome measure is change in comfortable walking speed from pre to post intervention for each group. We will also assess feasibility, adherence, postintervention efficacy, and changes in various exploratory secondary outcome measures. Additionally, we will also assess participant responses to a study survey, conducted at the end of training week, to gauge each group's training experiences.

Conclusions

Our treadmill training paradigms, and study protocol represent advances in standardized approaches to selecting body weight support levels without the necessity for using handrails or manual assistance, while progressively providing dynamic challenges for improving poststroke ambulatory function during rehabilitation.

Trial Registration

ClinicalTrials.gov NCT02787759; https://clinicaltrials.gov/ct2/show/NCT02787759 (Archived by Webcite at http://www.webcitation.org/6yJZCrIea)

Aerobic Exercise Prescription in Stroke Rehabilitation: A Web-Based Survey of US Physical Therapists

BACKGROUND AND PURPOSE

Best practice recommendations indicate that aerobic exercise (AEX) should be incorporated into stroke rehabilitation. However, this may be challenging in clinical settings. The purpose of this study was to assess physical therapist (PT) AEX prescription for patients with stroke, including AEX utilization, barriers to AEX prescription, dosing parameters, and safety considerations.

METHODS

A cross-sectional Web-based survey study was conducted. Physical therapists with valid e-mail addresses on file with the state boards of Florida, New Jersey, Ohio, Texas, and Wyoming were eligible to participate. Survey invitations were e-mailed to all licensed PT in these states. Analysis focused on respondents who were currently involved with clinical stroke rehabilitation in common practice settings.

RESULTS

Results from 568 respondents were analyzed. Most respondents (88%) agreed that AEX should be incorporated into stroke rehabilitation, but 84% perceived at least one barrier. Median prescribed AEX volume varied between practice settings from 20- to 30-minute AEX sessions, 3 to 5 days per week for 2 to 8 weeks. Prescribed intensity was most commonly light or moderate; intensity was determined by the general response to AEX and patient feedback. Only 2% of respondents reported that the majority of their patients with stroke had stress tests.

DISCUSSION AND CONCLUSIONS

Most US PTs appear to recognize the importance of AEX for persons poststroke, but clinical implementation can be challenging. Future studies and consensus are needed to clarify best practices and to develop implementation interventions to optimize AEX utilization in stroke rehabilitation.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A167).

Alterations in Aerobic Exercise Performance and Gait Economy Following High-Intensity Dynamic Stepping Training in Persons With Subacute Stroke

BACKGROUND AND PURPOSE

Impairments in metabolic capacity and economy (O2cost) are hallmark characteristics of locomotor dysfunction following stroke. High-intensity (aerobic) training has been shown to improve peak oxygen consumption in this population, with fewer reports of changes in O2cost. However, particularly in persons with subacute stroke, inconsistent gains in walking function are observed with minimal associations with gains in metabolic parameters. The purpose of this study was to evaluate changes in aerobic exercise performance in participants with subacute stroke following high-intensity variable stepping training as compared with conventional therapy.

METHODS

A secondary analysis was performed on data from a randomized controlled trial comparing high-intensity training with conventional interventions, and from the pilot study that formed the basis for the randomized controlled trial. Participants 1 to 6 months poststroke received 40 or fewer sessions of high-intensity variable stepping training (n = 21) or conventional interventions (n = 12). Assessments were performed at baseline (BSL), posttraining, and 2- to 3-month follow-up and included changes in submaximal (Equation is included in full-text article.)O2 ((Equation is included in full-text article.)O2submax) and O2cost at fastest possible treadmill speeds and peak speeds at BSL testing.

RESULTS

Significant improvements were observed in (Equation is included in full-text article.)O2submax with less consistent improvements in O2cost, although individual responses varied substantially. Combined changes in both (Equation is included in full-text article.)O2submax and (Equation is included in full-text article.)O2 at matched peak BSL speeds revealed stronger correlations to improvements in walking function as compared with either measure alone.

DISCUSSION AND CONCLUSIONS

High-intensity stepping training may elicit significant improvements in (Equation is included in full-text article.)O2submax, whereas changes in both peak capacity and economy better reflect gains in walking function. Providing high-intensity training to improve locomotor and aerobic exercise performance may increase the efficiency of rehabilitation sessions.Video Abstract available for more insights from the authors (see Supplemental Digital Content, http://links.lww.com/JNPT/A142).

Preliminary safety analysis of high-intensity interval training (HIIT) in persons with chronic stroke

The purpose of this study was to assess safety via electrocardiographic (ECG), blood pressure (BP), heart rate (HR), and orthopedic responses to 3 different high-intensity interval training (HIIT) protocols in persons with stroke. Eighteen participants (10 male; 61.9 + 8.3 years of age; 5.8 + 4.2 years poststroke) completed a symptom-limited graded exercise test (GXT) with ECG monitoring to screen for eligibility and determine HR peak. The 3 HIIT protocols involved repeated 30 s bursts of treadmill walking at maximum speed alternated with rest periods of 30 s (P30), 1 min (P60), or 2 min (P120). Sessions were performed in random order and included 5 min warm up, 20 min HIIT, and 5 min cool down. Variables measured included ECG activity, BP, HR, signs and symptoms of cardiovascular intolerance, and orthopedic concerns. Generalized linear mixed models and Tukey–Kramer adjustment were used to compare protocols using p < 0.05. No signs or symptoms of cardiovascular intolerance, significant arrhythmias, ST segment changes, or orthopedic responses resulted in early termination of any HIIT session. HIIT elicited HRs in excess of 88% of measured HRpeak including 6 (P30), 8 (P60), and 2 (P120) participants eliciting a HR response above their GXT HRpeak. Both maximum BP and HR were significantly higher in P30 and P60 relative to P120. Preliminary data indicate that persons with chronic stroke who have been prescreened with an ECG stress test, a symptom-limited GXT, and a harness for fall protection may safely participate in HIIT, generating substantially higher HRs than what is seen in traditional moderate intensity training.

High-Intensity Locomotor Exercise Increases Brain-Derived Neurotrophic Factor in Individuals with Incomplete Spinal Cord Injury

High-intensity locomotor exercise is suggested to contribute to improved recovery of locomotor function after neurological injury. This may be secondary to exercise-intensity-dependent increases in neurotrophin expression demonstrated previously in control subjects. However, rigorous examination of intensity-dependent changes in neurotrophin levels is lacking in individuals with motor incomplete spinal cord injury (SCI). Therefore, the primary aim of this study was to evaluate the effect of locomotor exercise intensity on peripheral levels of brain-derived neurotrophic factor (BDNF) in individuals with incomplete SCI. We also explored the impact of the Val66Met single-nucleotide polymorphism (SNP) on the BDNF gene on intensity-dependent changes. Serum concentrations of BDNF and insulin-like growth factor-1 (IGF-1), as well as measures of cardiorespiratory dynamics, were evaluated across different levels of exercise intensity achieved during a graded-intensity, locomotor exercise paradigm in 11 individuals with incomplete SCI. Our results demonstrate a significant increase in serum BDNF at high, as compared to moderate, exercise intensities (p = 0.01) and 15 and 30 min post-exercise (p < 0.01 for both), with comparison to changes at low intensity approaching significance (p = 0.05). Serum IGF-1 demonstrated no intensity-dependent changes. Significant correlations were observed between changes in BDNF and specific indicators of exercise intensity (e.g., rating of perceived exertion; R = 0.43; p = 0.02). Additionally, the data suggest that Val66Met SNP carriers may not exhibit intensity-dependent changes in serum BDNF concentration. Given the known role of BDNF in experience-dependent neuroplasticity, these preliminary results suggest that exercise intensity modulates serum BDNF concentrations and may be an important parameter of physical rehabilitation interventions after neurological injury.

Effects of Locomotor Exercise Intensity on Gait Performance in Individuals With Incomplete Spinal Cord Injury

BACKGROUND

High-intensity stepping practice may be a critical component to improve gait following motor incomplete spinal cord injury (iSCI). However, such practice is discouraged by traditional theories of rehabilitation that suggest high-intensity locomotor exercise degrades gait performance. Accordingly, such training is thought to reinforce abnormal movement patterns, although evidence to support this notion is limited.

OBJECTIVE

The purposes of this study were: (1) to evaluate the effects of short-term manipulations in locomotor intensity on gait performance in people with iSCI and (2) to evaluate potential detrimental effects of high-intensity locomotor training on walking performance.

DESIGN

A single-day, repeated-measures, pretraining-posttraining study design was used.

METHODS

Nineteen individuals with chronic iSCI performed a graded-intensity locomotor exercise task with simultaneous collection of lower extremity kinematic and electromyographic data. Measures of interest were compared across intensity levels of 33%, 67%, and 100% of peak gait speed. A subset of 9 individuals participated in 12 weeks of high-intensity locomotor training. Similar measurements were collected and compared between pretraining and posttraining evaluations.

RESULTS

The results indicate that short-term increases in intensity led to significant improvements in muscle activity, spatiotemporal metrics, and joint excursions, with selected improvements in measures of locomotor coordination. High-intensity locomotor training led to significant increases in peak gait speed (0.64-0.80 m/s), and spatiotemporal and kinematic metrics indicate a trend for improved coordination.

LIMITATIONS

Measures of gait performance were assessed during treadmill ambulation and not compared with a control group. Generalizability of these results to overground ambulation is unknown.

CONCLUSIONS

High-intensity locomotor exercise and training does not degrade, but rather improves, locomotor function and quality in individuals with iSCI, which contrasts with traditional theories of motor dysfunction following neurologic injury.

Strength Training for Skeletal Muscle Endurance after Stroke

BACKGROUND AND PURPOSE

Initial studies support the use of strength training (ST) as a safe and effective intervention after stroke. Our previous work shows that relatively aggressive, higher intensity ST translates into large effect sizes for paretic and non-paretic leg muscle volume, myostatin expression, and maximum strength post-stroke. An unanswered question pertains to how our unique ST model for stroke impacts skeletal muscle endurance (SME). Thus, we now report on ST-induced adaptation in the ability to sustain isotonic muscle contraction.

METHODS

Following screening and baseline testing, hemiparetic stroke participants were randomized to either ST or an attention-matched stretch control group (SC). Those in the ST group trained each leg individually to muscle failure (20 repetition sets, 3× per week for 3 months) on each of three pneumatic resistance machines (leg press, leg extension, and leg curl). Our primary outcome measure was SME, quantified as the number of submaximal weight leg press repetitions possible at a specified cadence. The secondary measures included one-repetition maximum strength, 6-minute walk distance (6MWD), 10-meter walk speeds, and peak aerobic capacity (VO₂ peak).

RESULTS

ST participants (N = 14) had significantly greater SME gains compared with SC participants (N = 16) in both the paretic (178% versus 12%, P < .01) and non-paretic legs (161% versus 12%, P < .01). These gains were accompanied by group differences for 6MWD (P < .05) and VO₂ peak (P < .05).

CONCLUSION

Our ST regimen had a large impact on the capacity to sustain submaximal muscle contraction, a metric that may carry more practical significance for stroke than the often reported measures of maximum strength.

Intensive cycle ergometer training improves gait speed and endurance in patients with Parkinson's disease: A comparison with treadmill training

PURPOSE

Cycle ergometer training improves gait in the elderly, but its effect in patients with Parkinson's disease (PD) is not completely known.

METHODS

Twenty-nine PD inpatients were randomized to treadmill (n = 13, PD-T) or cycle ergometer (n = 16, PD-C) training for 3 weeks, 1 hour/day. Outcome measures were distance travelled during the 6-min walking test (6MWT), spatio-temporal variables of gait assessed by baropodometry, the Timed Up and Go (TUG) duration, the balance score through the Mini-BESTest, and the score of the Unified Parkinson's Disease Rating Scale (UPDRS).

RESULTS

Sex, age, body mass index, disease duration, Hoehn-Yahr staging, comorbidity and medication did not differ between groups. At end of training, ANCOVA showed significant improvement, of similar degree, in both groups for 6MWT, speed, step length and cadence of gait, TUG, Mini-BESTest and UPDRS.

CONCLUSIONS

This pilot study shows that cycle ergometer training improves walking parameters and reduces clinical signs of PD, as much as treadmill training does. Gait velocity is accompanied by step lengthening, making the gait pattern close to that of healthy subjects. Cycle ergometer is a valid alternative to treadmill for improving gait in short term in patients with PD.

High-Intensity Interval Training and Moderate-Intensity Continuous Training in Ambulatory Chronic Stroke: Feasibility Study

BACKGROUND

Poststroke guidelines recommend moderate-intensity, continuous aerobic training (MCT) to improve aerobic capacity and mobility after stroke. High-intensity interval training (HIT) has been shown to be more effective than MCT among healthy adults and people with heart disease. However, HIT and MCT have not been compared previously among people with stroke.

OBJECTIVE

The purpose of this study was to assess the feasibility and justification for a definitive randomized controlled trial (RCT) comparing HIT and MCT in people with chronic stroke.

DESIGN

A preliminary RCT was conducted.

SETTING

The study was conducted in a cardiovascular stress laboratory and a rehabilitation research laboratory.

PATIENTS

Ambulatory people at least 6 months poststroke participated.

INTERVENTION

Both groups trained 25 minutes, 3 times per week, for 4 weeks. The HIT strategy involved 30-second bursts at maximum-tolerated treadmill speed alternated with 30- to 60-second rest periods. The MCT strategy involved continuous treadmill walking at 45% to 50% of heart rate reserve.

MEASUREMENTS

Measurements included recruitment and attendance statistics, qualitative HIT acceptability, adverse events, and the following blinded outcome variables: peak oxygen uptake, ventilatory threshold, metabolic cost of gait, fractional utilization, fastest treadmill speed, 10-Meter Walk Test, and Six-Minute Walk Test.

RESULTS

During the 8-month recruitment period, 26 participants consented to participate. Eighteen participants were enrolled and randomly assigned to either the HIT group (n=13) or the MCT group (n=5). Eleven out of the 13 HIT group participants attended all sessions. Participants reported that HIT was acceptable and no serious adverse events occurred. Standardized effect size estimates between groups were moderate to very large for most outcome measures. Only 30% of treadmill speed gains in the HIT group translated into overground gait speed improvement.

LIMITATIONS

The study was not designed to definitively test safety or efficacy.

CONCLUSIONS

Although further protocol optimization is needed to improve overground translation of treadmill gains, a definitive RCT comparing HIT and MCT appears to be feasible and warranted.

Ventilatory threshold may be a more specific measure of aerobic capacity than peak oxygen consumption rate in persons with stroke

BACKGROUND

After stroke, aerobic deconditioning can have a profound impact on daily activities. This is usually measured by the peak oxygen consumption rate achieved during exercise testing (VO2-peak). However, VO2-peak may be distorted by motor function. The oxygen uptake efficiency slope (OUES) and VO2 at the ventilatory threshold (VO2-VT) could more specifically assess aerobic capacity after stroke, but this has not been tested.

OBJECTIVES

To assess the differential influence of motor function on three measures of aerobic capacity (VO2-peak, OUES, and VO2-VT) and to evaluate the inter-rater reliability of VO2-VT determination post-stroke.

METHODS

Among 59 persons with chronic stroke, cross-sectional correlations with motor function (comfortable gait speed [CGS] and lower extremity Fugl-Meyer [LEFM]) were compared between the different aerobic capacity measures, after adjustment for covariates, in order to isolate any distorting effect of motor function. Reliability of VO2-VT determination between three raters was assessed with intra-class correlation (ICC).

RESULTS

CGS was moderately correlated with VO2-peak (r = 0.52, p < 0.0001) and weakly correlated with OUES (r = 0.41, p = 0.002) and VO2-VT (r = 0.37, p = 0.01). LEFM was weakly correlated with VO2-peak (r = 0.26, p = 0.055) and very weakly correlated with OUES (r = 0.19, p = 0.17) and VO2-VT (r = 0.14, p = 0.31). Compared to VO2-peak, VO2-VT was significantly less correlated with CGS (r difference = -0.16, p = 0.02). Inter-rater reliability of VO2-VT determination was high (ICC: 0.93, 95% CI: 0.89-0.96).

CONCLUSIONS

Motor dysfunction appears to artificially lower measured aerobic capacity. VO2-VT seemed to be less distorted than VO2-peak and had good inter-rater reliability, so it may provide more specific assessment of aerobic capacity post-stroke.

Stroke patients and long-term training: is it worthwhile? A randomized comparison of two different training strategies after rehabilitation

Objective : To find out if there were any differences in improvement and maintenance of motor function, activity of daily living and grip strength between patients with first-ever stroke receiving two different strategies of physical exercise during the first year after stroke.

Design : A longitudinal randomized controlled stratified trial.

Setting : Rehabilitation institutions, community, patients' homes and nursing homes.

Subjects : Seventy-five male and female first-time-ever stroke patients: 35 in an intensive exercise group and 40 in a regular exercise group.

Intervention : The intensive exercise group received physiotherapy with focus on intensive exercises in four periods during the first year after stroke. The regular exercise group patients were followed up according to their subjective needs during the corresponding year.

Main outcome measures : Motor Assessment Scale, Barthel Index of Activities of Daily Living, and grip strength.

Results : Both groups improved significantly up to six months when function stabilized. The groups did not differ significantly on any test occasions. The difference of improvement from admission to discharge was significant in favour of the intensive exercise group, in the Motor Assessment Scale total score (intensive exercise group 7.5; regular exercise group 1.7, P = 0.01), and in the Barthel Index of Activities of Daily Living total score (17.4 versus 8.9, P = 0.04).

Conclusion : Motor function, activities of daily living functions and grip strength improved initially and were maintained during the first year after stroke in all patients irrespective of exercise regime. This indicates the importance of motivation for regular exercise in the first year following stroke, achieved by regular check-ups.

Jump training is feasible for nearly ambulatory patients after stroke

Objective: To evaluate the feasibility of jump training for nearly ambulatory patients after stroke.

Design: Case series.

Setting: A rehabilitation centre for adult people with neurological disorders.

Subjects: Six subacute, nearly ambulatory patients with hemiparesis due to stroke.

Interventions: A modified form of jump training performed over a period of six weeks.

Measures: Impairments: We used the Motricity Index to measure strength, the Fugl-Meyer subtest passive joint motion/pain for range of motion and pain and the modified Tardieu Scale to measure spasticity at baseline and after six weeks. Activity level: To assess walking ability we used the Functional Ambulation Category, to measure walking quality we used 10-m gait velocity, stride length and Rivermead Visual Gait Index and to assess walking capacity we used the six-minute walk test.

Results: No severe adverse events were observed during the study period. Motricity Index sum score of the affected leg increased from 38±11 points (mean±SD) to 56±15 points; P = 0.028. Modified Tardieu Scale and Fugl-Meyer subtest passive joint motion/pain remained unchanged over time (P=1.0; P=0.157, respectively). All patients were able to walk at the end of training (median Functional Ambulation Category grade five, P=0.023). Gait quality improved as shown in increased gait velocity (from 0.3±0.1 to 1.1±0.5 m/s; P = 0.028), improved stride length (from 0.3±0.1 to 0.6±0.2 m; P = 0.028) and improved Rivermead Visual Gait Index score (from 38.7±5.6 points to 24.8±7.0 points; P = 0.027). All patient increased gait capacity (from 97±33 m to 289±134 m; P = 0.028).

Conclusion: Jump exercises are feasible for selected subacute stroke patients with hemiparesis.

Decreased tidal volume may limit cardiopulmonary performance during exercise in subacute stroke

PURPOSE

The aim of this retrospective study was to determine whether pulmonary function was reduced at submaximal and peak exercise in subacute stroke (SG) when compared with sedentary adults (CON).

METHODS

Ten individuals with subacute stroke and 10 sedentary, age- and gender-matched adults performed cardiopulmonary exercise testing (CPET), using a recumbent stepper. We used independent t tests to determine between-group differences at peak effort. We used repeated-measures analysis of variance with Test Minute (minutes 1-6) as the within-subject factor and Group (SG, CON) as the between-subject factor to assess cardiopulmonary submaximal performance.

RESULTS

The SG had significantly lower values (P < .05) for oxygen uptake, minute ventilation ((Equation is included in full-text article.)E), and tidal volume (VT) than CON at peak effort of the CPET. During CPET submaximal effort, we report a significant main effect for Test Minute and Group for VT and respiratory rate but no main effect of Group for (Equation is included in full-text article.)E. To maintain adequate (Equation is included in full-text article.)E during submaximal effort and decreased VT, higher respiratory rate was observed.

CONCLUSIONS

These results suggest that diminished VT in subacute stroke patients may limit performance during submaximal and peak effort of CPET. Rehabilitation professionals should consider methods for improving pulmonary function during stroke rehabilitation.

Rapid Responsiveness to Practice Predicts Longer-Term Retention of Upper Extremity Motor Skill in Non-Demented Older Adults

Skill acquisition is a form of motor learning that may provide key insights into the aging brain. Although previous work suggests that older adults learn novel motor tasks slower and to a lesser extent than younger adults, we have recently demonstrated no significant effect of chronological age on the rates and amounts of skill acquisition, nor on its long-term retention, in adults over the age of 65. To better understand predictors of skill acquisition in non-demented older adults, we now explore the relationship between early improvements in motor performance due to practice (i.e., rapid responsiveness) and longer-term retention of an upper extremity motor skill, and whether the extent of rapid responsiveness was associated with global cognitive status. Results showed significant improvements in motor performance within the first five (of 150) trials, and that this “rapid responsiveness” was predictive of skill retention 1 month later. Notably, the extent of rapid responsiveness was not dependent on global cognitive status, as measured by the Montreal Cognitive Assessment (MoCA). Thus, rapid responsiveness appears to be an important variable in longer-term neurorehabilitative efforts with older adults, regardless of their cognitive status.

Predicting Heart Rate at the Ventilatory Threshold for Aerobic Exercise Prescription in Persons With Chronic Stroke

BACKGROUND AND PURPOSE

Treadmill aerobic exercise improves gait, aerobic capacity, and cardiovascular health after stroke, but a lack of specificity in current guidelines could lead to underdosing or overdosing of aerobic intensity. The ventilatory threshold (VT) has been recommended as an optimal, specific starting point for continuous aerobic exercise. However, VT measurement is not available in clinical stroke settings. Therefore, the purpose of this study was to identify an accurate method to predict heart rate at the VT (HRVT) for use as a surrogate for VT.

METHODS

A cross-sectional design was employed. Using symptom-limited graded exercise test (GXT) data from 17 subjects more than 6 months poststroke, prediction methods for HRVT were derived by traditional target HR calculations (percentage of HRpeak achieved during GXT, percentage of peak HR reserve [HRRpeak], percentage of age-predicted maximal HR, and percentage of age-predicted maximal HR reserve) and by regression analysis. The validity of the prediction methods was then tested among 8 additional subjects.

RESULTS

All prediction methods were validated by the second sample, so data were pooled to calculate refined prediction equations. HRVT was accurately predicted by 80% HRpeak (R, 0.62; standard deviation of error [SDerror], 7 bpm), 62% HRRpeak (R, 0.66; SDerror, 7 bpm), and regression models that included HRpeak (R, 0.62-0.75; SDerror, 5-6 bpm).

DISCUSSION AND CONCLUSIONS

Derived regression equations, 80% HRpeak and 62% HRRpeak, provide a specific target intensity for initial aerobic exercise prescription that should minimize underdosing and overdosing for persons with chronic stroke. The specificity of these methods may lead to more efficient and effective treatment for poststroke deconditioning.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A114).

Within-session responses to high-intensity interval training in chronic stroke

Poststroke hemiparesis often leads to a vicious cycle of limited activity, deconditioning, and poor cardiovascular health. Accumulating evidence suggests that exercise intensity is a critical factor determining gains in aerobic capacity, cardiovascular protection, and functional recovery after stroke. High-intensity interval training (HIT) is a strategy that augments exercise intensity using bursts of concentrated effort alternated with recovery periods. However, there was previously no stroke-specific evidence to guide HIT protocol selection.

PURPOSE

This study aimed to compare within-session exercise responses among three different HIT protocols for persons with chronic (>6 months after) stroke.

METHODS

Nineteen ambulatory persons with chronic stroke performed three different 1-d HIT sessions in a randomized order, approximately 1 wk apart. HIT involved repeated 30-s bursts of treadmill walking at maximum tolerated speed, alternated with rest periods. The three HIT protocols were different on the basis of the length of the rest periods, as follows: 30 s (P30), 60 s (P60), or 120 s (P120). Exercise tolerance, oxygen uptake (V˙O2), HR, peak treadmill speed, and step count were measured.

RESULTS

P30 achieved the highest mean V˙O2, HR, and step count but with reduced exercise tolerance and lower treadmill speed than P60 or P120 (P30: 70.9% V˙O2peak, 76.1% HR reserve (HRR), 1619 steps, 1.03 m·s(-1); P60: 63.3% V˙O2peak, 63.1% HRR, 1370 steps, 1.13 m·s(-1); P120: 47.5% V˙O2peak, 46.3% HRR, 1091 steps, 1.10 m·s(-1)). P60 achieved treadmill speed and exercise tolerance similar to those in P120, with higher mean V˙O2, HR, and step count.

CONCLUSIONS

For treadmill HIT in chronic stroke, a combination of P30 and P60 may optimize aerobic intensity, treadmill speed, and stepping repetition, potentially leading to greater improvements in aerobic capacity and gait outcomes in future studies.

Does aerobic exercise and the FITT principle fit into stroke recovery?

Sedentary lifestyle after stroke is common which results in poor cardiovascular health. Aerobic exercise has the potential to reduce cardiovascular risk factors and improve functional capacity and quality of life in people after stroke. However, aerobic exercise is a therapeutic intervention that is underutilized by healthcare professionals after stroke. The purpose of this review paper is to provide information on exercise prescription using the FITT principle (frequency, intensity, time, type) for people after stroke and to guide healthcare professionals to incorporate aerobic exercise into the plan of care. This article discusses the current literature outlining the evidence base for incorporating aerobic exercise into stroke rehabilitation. Recently, high-intensity interval training has been used with people following stroke. Information is provided regarding the early but promising results for reaching higher target heart rates.

Classifying physical activity research following stroke using the behavioral epidemiologic framework

BACKGROUND

Stroke is a significant public health issue in the USA and a need emerges to better understand how to reduce an individual's co-morbidity risk. Physical activity is one approach to improving the health of individuals and comprehensive literature supports increased activity as a means to reduce risk of morbidity and mortality. One approach to examining whether research in a field is addressing a public health issue is through application of the behavioral epidemiological framework.

OBJECTIVE

To classify physical activity research for individuals following stroke into distinct phases so that efforts can be made to systematically address gaps and disseminate evidence-based practice.

METHODS

Specific key words were identified and then searched through EBSCO host, PubMed, and Google Scholar. Physical activity and stroke literature from 2000-2014 was categorized into one of five discrete phases. Research in Phase 1 identified associations between activity and health; Phase 2 established valid measures of activity; Phase 3 examined determinants of behavior; Phase 4 evaluated activity interventions; and Phase 5 disseminated evidence-based practice.

RESULTS

A comprehensive review of literature identified 202 articles with 70% categorized in Phase 1 (n = 141), 11% in Phase 2 (n = 23), 10% in Phase 3 (n = 20), 8% in Phase 4 (n = 15), and 1% in Phase 5 (n = 3).

CONCLUSION

Findings suggest that physical activity research for individuals following stroke is in the early stages of development with less than 10% of research evaluating or disseminating interventions.

Ottawa Panel Evidence-Based Clinical Practice Guidelines for Post-Stroke Rehabilitation

BACKGROUND AND PURPOSE

The purpose of this project was to create guidelines for 13 types of physical rehabilitation interventions used in the management of adult patients (>18 years of age) presenting with hemiplegia or hemiparesis following a single clinically identifiable ischemic or hemorrhagic cerebrovascular accident (CVA).

METHOD

Using Cochrane Collaboration methods, the Ottawa Methods Group identified and synthesized evidence from comparative controlled trials. The group then formed an expert panel, which developed a set of criteria for grading the strength of the evidence and the recommendation. Patient-important outcomes were determined through consensus, provided that these outcomes were assessed with a validated and reliable scale.

RESULTS

The Ottawa Panel developed 147 positive recommendations of clinical benefit concerning the use of different types of physical rehabilitation interventions involved in post-stroke rehabilitation.

DISCUSSION AND CONCLUSION

The Ottawa Panel recommends the use of therapeutic exercise, task-oriented training, biofeedback, gait training, balance training, constraint-induced movement therapy, treatment of shoulder subluxation, electrical stimulation, transcutaneous electrical nerve stimulation, therapeutic ultrasound, acupuncture, and intensity and organization of rehabilitation in the management of post stroke.

Post-Stroke Consultation Service: A Nurse-Managed Model for Care Delivery

In 1989, a multidisciplinary consultation service devoted to providing primary care and rehabilitative care services to stroke survivors in the home was developed and tested at the University of Pennsylvania. This nurse-managed service, Post-Stroke Consultation Service, used the expertise of a nurse practitioner, geriatrician, physiatrist, physical therapists, home health care nurses, specialty care providers, families, and stroke survivors to develop and implement a plan of care that optimized health and function and would be sustainable over time. The service and its impact are described.

Ambulatory Activity Intensity Profiles, Fitness, and Fatigue in Chronic Stroke

PURPOSE

The purpose of this study was to describe household and community ambulatory activity profiles and their relationship to fatigue and cardiovascular fitness in a sample of men and women with chronic hemiparetic stroke.

METHOD

We quantified community-based ambulatory activity profiles in terms of step counts and intensity, along with cardiovascular fitness and fatigue severity, in a convenience sample of 79 men and women with chronic hemiparetic stroke.

RESULTS

As captured by daily step activity monitoring, participants demonstrated extremely low step counts (1389 +/- 797 steps/day), and almost no step activity at high intensity (78 +/- 168 steps/day at a rate of >or=30 steps/ minute). Mean high intensity activity constituted less than 3 minutes/day. The mean VO2 peak was 13.02 +/- 4.26 mL/kg/min, consistent with profound aerobic deconditioning. Total, low, and high intensity ambulatory activity were associated with VO2 peak. Mean fatigue severity was 3.28 +/- 1.36 on a scale of 7.00, with 42% of the sample reporting severe fatigue. There were no statistically significant correlations between fatigue severity and ambulatory activity or fitness measures.

CONCLUSION

Our results show that step activity intensity is strongly associated with cardiovascular fitness, lending credence to the hypothesis that rehabilitation interventions that build aerobic conditioning can influence daily activity. The challenge is to appreciate the features of ambulatory behavior after stroke and to use this information to integrate both exercise interventions and behavioral components into the successful translation of structured activities into home and community routines.

Effects of dynamic stepping training on nonlocomotor tasks in individuals poststroke

BACKGROUND

During the physical rehabilitation of individuals poststroke, therapists are challenged to provide sufficient amounts of task-specific practice in order to maximize outcomes of multiple functional skills within limited visits. Basic and applied studies have suggested that training of one motor task may affect performance of biomechanically separate tasks that utilize overlapping neural circuits. However, few studies have explicitly investigated the impact of training one functional task on separate, nonpracticed tasks.

OBJECTIVE

The purpose of this preliminary study was to investigate the potential gains in specific nonlocomotor assessments in individuals poststroke following only stepping training of variable, challenging tasks at high aerobic intensities.

METHODS

Individuals with locomotor deficits following subacute and chronic stroke (n=22) completed a locomotor training paradigm using a repeated-measures design. Practice of multiple stepping tasks was provided in variable environments or contexts at high aerobic intensities for ≥40 sessions over 10 weeks. The primary outcome was timed Five-Times Sit-to-Stand Test (5XSTS) performance, with secondary measures of sit-to-stand kinematics and kinetics, clinical assessment of balance, and isometric lower limb strength.

RESULTS

Participants improved their timed 5XSTS performance following stepping training, with changes in selected biomechanical measures. Statistical and clinically meaningful improvements in balance were observed, with more modest changes in paretic leg strength.

CONCLUSIONS

The present data suggest that significant gains in selected nonlocomotor tasks can be achieved with high-intensity, variable stepping training. Improvements in nonpracticed tasks may minimize the need to practice multiple tasks within and across treatment sessions.

Concurrent validity of Physiological Cost Index in walking over ground and during robotic training in subacute stroke patients

Physiological Cost Index (PCI) has been proposed to assess gait demand. The purpose of the study was to establish whether PCI is a valid indicator in subacute stroke patients of energy cost of walking in different walking conditions, that is, over ground and on the Gait Trainer (GT) with body weight support (BWS). The study tested if correlations exist between PCI and ECW, indicating validity of the measure and, by implication, validity of PCI. Six patients (patient group (PG)) with subacute stroke and 6 healthy age- and size-matched subjects as control group (CG) performed, in a random sequence in different days, walking tests overground and on the GT with 0, 30, and 50% BWS. There was a good to excellent correlation between PCI and ECW in the observed walking conditions: in PG Pearson correlation was 0.919 (p < 0.001); in CG Pearson correlation was 0.852 (p < 0.001). In conclusion, the high significant correlations between PCI and ECW, in all the observed walking conditions, suggest that PCI is a valid outcome measure in subacute stroke patients.

Physiological responses and energy cost of walking on the Gait Trainer with and without body weight support in subacute stroke patients

Background

Robotic-assisted walking after stroke provides intensive task-oriented training. But, despite the growing diffusion of robotic devices little information is available about cardiorespiratory and metabolic responses during electromechanically-assisted repetitive walking exercise. Aim of the study was to determine whether use of an end-effector gait training (GT) machine with body weight support (BWS) would affect physiological responses and energy cost of walking (ECW) in subacute post-stroke hemiplegic patients.

Methods

Participants: six patients (patient group: PG) with hemiplegia due to stroke (age: 66 ± 15y; time since stroke: 8 ± 3 weeks; four men) and 6 healthy subjects as control group (CG: age, 76 ± 7y; six men).

Interventions: overground walking test (OWT) and GT-assisted walking with 0%, 30% and 50% BWS (GT-BWS0%, 30% and 50%). Main Outcome Measures: heart rate (HR), pulmonary ventilation, oxygen consumption, respiratory exchange ratio (RER) and ECW.

Results

Intervention conditions significantly affected parameter values in steady state (HR: p = 0.005, V’E: p = 0.001, V'O₂: p < 0.001) and the interaction condition per group affected ECW (p = 0.002). For PG, the most energy (V’O₂ and ECW) demanding conditions were OWT and GT-BWS0%. On the contrary, for CG the least demanding condition was OWT. On the GT, increasing BWS produced a decrease in energy and cardiac demand in both groups.

Conclusions

In PG, GT-BWS walking resulted in less cardiometabolic demand than overground walking. This suggests that GT-BWS walking training might be safer than overground walking training in subacute stroke patients.

Community-based exercise for upper limb paresis: a controlled trial with telerehabilitation

BACKGROUND

Arm paresis remains a major impairment after stroke despite the best conventional rehabilitation. Randomized, controlled trials of intensive exercise programs have demonstrated improvements in arm function for patients with chronic stroke. However, the gains achieved have been relatively modest for the large investments in patient and therapist time.

OBJECTIVE

To evaluate the safety, acceptance, adherence, and effectiveness of a community-based exercise program for upper limb paresis in patients with chronic stroke and the effects of telerehabilitation monitoring in kiosks distributed through the community.

METHODS

Longitudinal cohort with geographic control group. The experimental group received devices needed for a home exercise program based on the Carr and Shepherd "Motor Learning Program" and were instructed to practice the exercises at least twice a week at the kiosk and at least 3 more days a week at home. The control group received usual care.

RESULTS

Compared with the control group, patients in the experimental group demonstrated significant gains in arm function as measured by the Wolf Motor Function Test, 9-Hole Peg Test, Motricity Index, and Nottingham Extended Activities of Daily Living Questionnaire. The intervention received high satisfaction ratings and produced no adverse events. Only 30% of the subjects attended kiosks regularly. Outcomes for this group did not differ significantly from those who only practiced at home.

CONCLUSIONS

Home- and community-based exercise for arm paresis is safe and effective. Telerehabilitation interventions will need additional enhancements to improve effectiveness. The optimal upper extremity exercise prescription poststroke remains to be established.