Treadmill training improves fitness reserve in chronic stroke patients

Structured different exercise protocols improve lung function, respiratory muscle strength, and thickness in stroke patients. A randomized controlled trial

BACKGROUND

The effect of core stabilization exercises (CSE) alone, or in combination with neuromuscular electrical stimulation (NMES) and Kinesio taping (KT) on lung function, respiratory muscle strength, and thickness in patients with stroke is not fully known. ObjectivesTo compare the efficacy of NMES and KT applied with CSE on lung functions, respiratory muscle strength, and thickness in stroke.

OBJECTIVE

The effect of core stabilization exercises (CSE) alone, or in combination with neuromuscular electrical stimulation (NMES) and Kinesio taping (KT) on lung function, respiratory muscle strength, and thickness in patients with stroke is not fully known. The aim of this study was to compare the efficacy of NMES and KT applied with CSE on lung functions, respiratory muscle strength, and thickness in stroke.

METHODS

A total of 45 stroke patients were randomly assigned to the core stabilization exercises (CSE) group, CSE+KT group or CSE+NMES group, respectively. All groups received the training protocol for 30-45 minutes, 3 days a week, for 6 weeks. Lung functions were measured using portable spirometry. Respiratory muscle strength was assessed using an analog manometer to measure maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP). Peak cough flow (PCF) was measured with a peak flow meter. Respiratory muscles thickness were determined using ultrasonography.

RESULTS

Except for FVC (%pred%) (F = 4.432, p = 0.018, ηp  = 0.174), FEV1(%pred%) (F = 3.725, p = 0.032, ηp  = 0.151), and MEP (F = 3.861, p = 0.029, ηp  = 0.155), the overall group by time interaction for rmANOVA showed that there was no statistically significant difference between groups (p > 0.05). After post hoc analysis, it was determined that there was no statistically significant difference between the groups in terms of FVC (%pred%), FEV1(%pred%) and MEP (p > 0.025).

CONCLUSIONS

The addition of NMES or KT to core stabilization exercises did not appear to provide additional benefit in improving lung function, respiratory muscle strength, and thickness in stroke patients.

Reproducibility (reliability and agreement) of ventilatory threshold and peak responses during cardiopulmonary exercise test in people with stroke

BACKGROUND

A cardiopulmonary exercise test (CPET) is used to determine the ventilatory thresholds and to directly assess cardiorespiratory capacity. However, its reproducibility should be tested in people with stroke as sequelae imposed by the stroke may induce important variations among and within each subject, affecting the reproducibility of the physiological responses to CPET.

PURPOSE

This cross-sectional repeated measures study design aims to determine the reproducibility of anaerobic threshold (AT), respiratory compensation point (RCP), and maximal cardiorespiratory capacity assessed during a CPET in people with stroke.

METHODS

Twenty-eight subjects with hemiparesis after stroke aging 60 ± 13 years were submitted to two treadmill CPETs with identical protocols.

DATA ANALYSIS

The reproducibility of heart rate (HR) and oxygen consumption (VO2) obtained at AT, RCP, and peak effort was evaluated by systematic error (paired t-test); reliability (ICC and 95% confidence interval); and agreement (typical error and coefficient of variation).

RESULTS

There were no systematic errors for HR and VO2assessed at AT, RCP, and peak effort (p  > 0,05). Reliability was high for these variables during CPET (ICCs > 0.93). Agreement was good for all variables. Typical errors for HR and VO2 assessed at AT, RCP, and peak effort were, respectively, 7, 7, and 8 bpm, and 1.51, 1.44, and 1.57 ml.kg-1.min-1. Coefficients of variation assessed at AT, RCP, and peak effort were, respectively, 5.7, 5.1, and 6.0% for HR and 8.7, 7.3, and 7.5% for VO2.

CONCLUSIONS

HR and VO2 measured at AT, RCP, and peak effort during a treadmill CPET present good reproducibility in people with stroke, showing high reliability and good agreement.

A Comprehensive Review of Physical Therapy Interventions for Stroke Rehabilitation: Impairment-Based Approaches and Functional Goals

Stroke is the fourth leading cause of mortality and is estimated to be one of the major reasons for long-lasting disability worldwide. There are limited studies that describe the application of physical therapy interventions to prevent disabilities in stroke survivors and promote recovery after a stroke. In this review, we have described a wide range of interventions based on impairments, activity limitations, and goals in recovery during different stages of a stroke. This article mainly focuses on stroke rehabilitation tactics, including those for sensory function impairments, motor learning programs, hemianopia and unilateral neglect, flexibility and joint integrity, strength training, hypertonicity, postural control, and gait training. We conclude that, aside from medicine, stroke rehabilitation must address specific functional limitations to allow for group activities and superior use of a hemiparetic extremity. Medical doctors are often surprised by the variety of physiotherapeutic techniques available; they are unfamiliar with the approaches of researchers such as Bobath, Coulter, and Brunnstrom, among others, as well as the scientific reasoning behind these techniques.

Relative Aerobic Load of Daily Activities After Stroke

OBJECTIVE

Individuals after stroke are less active, experience more fatigue, and perform activities at a slower pace than peers with no impairments. These problems might be caused by an increased aerobic energy expenditure during daily tasks and a decreased aerobic capacity after stroke. The aim of this study was to quantify relative aerobic load (ie, the ratio between aerobic energy expenditure and aerobic capacity) during daily-life activities after stroke.

METHODS

Seventy-nine individuals after stroke (14 in Functional Ambulation Category [FAC] 3, 25 in FAC 4, and 40 in FAC 5) and 22 peers matched for age, sex, and body mass index performed a maximal exercise test and 5 daily-life activities at a preferred pace for 5 minutes. Aerobic energy expenditure (mL O2/kg/min) and economy (mL O2/kg/unit of distance) were derived from oxygen uptake ($\dot{\mathrm{V}}{\mathrm{O}}_2$). Relative aerobic load was defined as aerobic energy expenditure divided by peak aerobic capacity (%$\dot{\mathrm{V}}{\mathrm{O}}_2$peak) and by $\dot{\mathrm{V}}{\mathrm{o}}_2$ at the ventilatory threshold (%$\dot{\mathrm{V}}{\mathrm{o}}_2$-VT) and compared in individuals after stroke and individuals with no impairments.

RESULTS

Individuals after stroke performed activities at a significantly higher relative aerobic load (39%-82% $\dot{\mathrm{V}}{\mathrm{o}}_2$peak) than peers with no impairments (38%-66% $\dot{\mathrm{V}}{\mathrm{o}}_2$peak), despite moving at a significantly slower pace. Aerobic capacity in individuals after stroke was significantly lower than that in peers with no impairments. Movement was less economical in individuals after stroke than in peers with no impairments.

CONCLUSION

Individuals after stroke experience a high relative aerobic load during cyclic daily-life activities, despite adopting a slower movement pace than peers with no impairments. Perhaps individuals after stroke limit their movement pace to operate at sustainable relative aerobic load levels at the expense of pace and economy.

IMPACT

Improving aerobic capacity through structured aerobic training in a rehabilitation program should be further investigated as a potential intervention to improve mobility and functioning after stroke.

The effect of exercise on walking economy in patients with chronic neurological conditions: A systematic review and meta-analysis

Introduction

To investigate the effect of exercise on the walking economy (WE) of patients with chronic neurological conditions (CNCs) and to determine the type of physical activity that best improves the WE of patients with CNCs.

Methods

Four electronic databases were searched until December 2022 (Web of Science, PubMed, Cochrane, and CINAHL). Studies were screened using the following inclusion criteria: 1. randomized controlled or non-randomized controlled trials; 2. exercise interventions >4 weeks in duration; 3. patients aged ≥18 years with a diagnosis of CNCs. 4. walking economy of patients measured before and after the intervention. The PEDro scale was used to assess the methodological quality of the included studies.

Results and discussion

Twenty-two studies met the inclusion criteria. Meta-analysis results showed that exercise significantly improved WE (g = -0.352, 95% CI, -0.625 to -0.078, P = 0.012). Subgroup analysis revealed that patients who received exercise showed better WE compared with those who underwent no control intervention (g = -0.474, 95% CI, -0.636 to -0.311, P < 0.001). However, exercise therapy did not show a significant improvement of WE compared with control groups (g = -0.192, 95% CI, -0.451 to 0.067, P = 0.146). In addition, we found that endurance combined with resistance, high-intensity intermittent, and other training modalities resulted in better WE compared with the pre-intervention. Of these, interval training has the greatest effect on improving WE. In conclusion, exercise can improve WE in patients with CNCs. More randomized controlled trials are necessary for the future.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022361455, identifier: CRD42022361455.

A Comparison of Three Common Rehabilitation Interventions Used to Improve Cardiovascular Fitness after Stroke: An Overview of the Literature

Background

One of the most frequent consequences of stroke is a reduction in heart function. After a stroke, one of the main aims of physiotherapy practice is to improve cardiovascular fitness (CVF). This paper is aimed at identifying the best effective intervention of improving the cardiovascular fitness (CVF) after stroke while focusing on body weight-supported treadmill training (BWSTT), over gait training (OGT), and therapeutic exercise.

Methods

Different electronic databases were searched until July 2022. Controlled randomized trials examining the effects of BWSTT, OGT, and therapeutic exercise to improve CVF on an ambulatory person with stroke, written in English and reporting cardiovascular fitness or at least one of its indicators, such as peak oxygen consumption (VO₂), gait speed, gait energy expenditure, and functional independence measure for locomotion (FIM-L), were included. The quality of the methodology was evaluated using the Physiotherapy Evidence Database (PEDro) scale.

Results

The research yielded 3854 relevant studies, of which 22 met the eligibility criteria. The primary indicators of the CVF, VO₂ and energy expenditure, were used to examine the CVF in only three studies, while the rest used other indicators of the CVF. There was a lack of sufficient evidence to establish the superiority of one intervention over another. However, it appears that utilizing BWSTT to improve the CVF after stroke is effective.

Conclusion

Physiotherapy has the potential to enhance the CVF of stroke patients. However, effective interventions and long-term effects remain debatable.

Comparison of the effectiveness of anti-gravity treadmill exercises and underwater walking exercises on cardiorespiratory fitness, functional capacity and balance in stroke patients

INTRODUCTION

Aerobic exercise training after stroke has positive effects on quality of life, motor recovery, and aerobic endurance. The aim of this study was to investigate the effectiveness of anti-gravity treadmill gait training and underwater walking therapy on cardiorespiratory fitness, gait and balance in stroke survivors.

METHODS

The study included 39 patients with a history of stroke who were admitted to our center between July 2017 and January 2018. The patients were randomly assigned to anti-gravity treadmill training, underwater walking therapy, or a control group. The aerobic capacity of the participants was evaluated with the 6-min walk test and cycle ergometer testing before and after the treatment. Balance was examined using the Berg Balance Scale (BBS).

RESULTS

There was a statistically significant increase from pre- to post-treatment with regard to maximum heart rate and length of walking distance during 6-min walk test parameters in patients who underwent anti-gravity treadmill training (p < 0.05). The cycle ergometer training results showed significant improvements compared to baseline after treatment in patients who underwent anti-gravity training in terms of maximum heart rate attained during exercise stress testing, time to complete the test, rates of metabolic equivalents of task scores and peak oxygen consumption (p < 0.05). Improvements were also observed in ventricular repolarization indices including corrected QT intervals (QTc), Tp-e interval and Tp-e/QT, Tp-e/QTc ratio in the anti-gravity group (p < 0.05). BBS results showed no statistically significant difference in all groups (p > 0.05).

CONCLUSION

The data of this study showed that anti-gravity treadmill training has favorable effects on cardiorespiratory fitness in stroke survivors.

Effect of Treadmill Training Interventions on Spatiotemporal Gait Parameters in Older Adults with Neurological Disorders: Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective: Treadmill interventions have been shown to promote ‘normal’ walking patterns, as they facilitate the proper movement and timing of the lower limbs. However, prior reviews have not examined which intervention provides the most effective treatment of specific gait impairments in neurological populations. The objective of this systematic review was to review and quantify the changes in gait after treadmill interventions in adults with neurological disorders. Data Sources: A keyword search was performed in four databases: PubMed, CINAHL, Scopus, and Web of Science (January 2000−December 2021). We performed the search algorithm including all possible combinations of keywords. Full-text articles were examined further using forward/backward search methods. Study Selection: Studies were thoroughly screened using the following inclusion criteria: study design: Randomized Controlled Trial (RCT); adults ≥55 years old with a neurological disorder; treadmill intervention; spatiotemporal gait characteristics; and language: English. Data Extraction: A standardized data extraction form was used to collect the following methodological outcome variables from each of the included studies: author, year, population, age, sample size, and spatiotemporal gait parameters including stride length, stride time, step length, step width, step time, stance time, swing time, single support time, double support time, or cadence. Data Synthesis: We found a total of 32 studies to be included in our systematic review through keyword search, out of which 19 studies included adults with stroke and 13 studies included adults with PD. We included 22 out of 32 studies in our meta-analysis that examined gait in adults with neurological disorders, which only yielded studies including Parkinson’s disease (PD) and stroke patients. A meta-analysis was performed among trials presenting with similar characteristics, including study population and outcome measure. If heterogeneity was >50% (denoted by I2), random plot analysis was used, otherwise, a fixed plot analysis was performed. All analyses used effect sizes and standard errors and a p < 0.05 threshold was considered statistically significant (denoted by *). Overall, the effect of treadmill intervention on cadence (z = 6.24 *, I2 = 11.5%) and step length (z = 2.25 *, I2 = 74.3%) in adults with stroke was significant. We also found a significant effect of treadmill intervention on paretic step length (z = 2.34 *, I2 = 0%) and stride length (z = 6.09 *, I2 = 45.5%). For the active control group, including adults with PD, we found that overground physical therapy training had the largest effect on step width (z = −3.75 *, I2 = 0%). Additionally, for PD adults in treadmill intervention studies, we found the largest significant effect was on step length (z = 2.73 *, I2 = 74.2%) and stride length (z = −2.54 *, I2 = 96.8%). Conclusion: Treadmill intervention with sensory stimulation and body weight support treadmill training were shown to have the largest effect on step length in adults with PD and stroke.

Associations Between Time After Stroke and Exercise Training Outcomes: A Meta-Regression Analysis

Background Knowledge gaps exist regarding the effect of time elapsed after stroke on the effectiveness of exercise training interventions, offering incomplete guidance to clinicians. Methods and Results To determine the associations between time after stroke and 6-minute walk distance, 10-meter walk time, cardiorespiratory fitness and balance (Berg Balance Scale score [BBS]) in exercise training interventions, relevant studies in post-stroke populations were identified by systematic review. Time after stroke as continuous or dichotomized (≤3 months versus >3 months, and ≤6 months versus >6 months) variables and weighted mean differences in postintervention outcomes were examined in meta-regression analyses adjusted for study baseline mean values (pre-post comparisons) or baseline mean values and baseline control-intervention differences (controlled comparisons). Secondary models were adjusted additionally for mean age, sex, and aerobic exercise intensity, dose, and modality. We included 148 studies. Earlier exercise training initiation was associated with larger pre-post differences in mobility; studies initiated ≤3 months versus >3 months after stroke were associated with larger differences (weighted mean differences [95% confidence interval]) in 6-minute walk distance (36.3 meters; 95% CI, 14.2-58.5), comfortable 10-meter walk time (0.13 m/s; 95% CI, 0.06-0.19) and fast 10-meter walk time (0.16 m/s; 95% CI, 0.03-0.3), in fully adjusted models. Initiation ≤3 months versus >3 months was not associated with cardiorespiratory fitness but was associated with a higher but not clinically important Berg Balance Scale score difference (2.9 points; 95% CI, 0.41-5.5). In exercise training versus control studies, initiation ≤3 months was associated with a greater difference in only postintervention 6-minute walk distance (baseline-adjusted 27.3 meters; 95% CI, 6.1-48.5; fully adjusted, 24.9 meters; 95% CI, 0.82-49.1; a similar association was seen for ≤6 months versus >6 months after stroke (fully adjusted, 26.6 meters; 95% CI, 2.6-50.6). Conclusions There may be a clinically meaningful benefit to mobility outcomes when exercise is initiated within 3 months and up to 6 months after stroke.

The relationship between relative aerobic load, energy cost, and speed of walking in individuals post-stroke

BACKGROUND

Individuals post-stroke walk slower than their able-bodied peers, which limits participation. This might be attributed to neurological impairments, but could also be caused by a mismatch between aerobic capacity and aerobic load of walking leading to an unsustainable relative aerobic load at most economic speed and preference for a lower walking speed.

RESEARCH QUESTION

What is the impact of aerobic capacity and aerobic load of walking on walking ability post-stroke?

METHODS

Forty individuals post-stroke (more impaired N = 21; preferred walking speed (PWS)<0.8 m/s, less impaired N = 19), and 15 able-bodied individuals performed five, 5-minute treadmill walking trials at 70 %, 85 %, 100 %, 115 % and 130 % PWS. Energy expenditure (mlO₂/kg/min) and energy cost (mlO₂/kg/m) were derived from oxygen uptake (V˙O₂). Relative load was defined as energy expenditure divided by peak aerobic capacity (%V˙O₂peak) and by V˙O₂ at ventilatory threshold (%V˙O₂-VT). Relative load and energy cost at PWS were compared with one-way ANOVA's. The effect of speed on these parameters was modeled with Generalized Estimating Equations.

RESULTS

Both more and less impaired individuals post-stroke showed lower PWS than able-bodied controls (0.44 [0.19-0.76] and 1.04 [0.81-1.43] vs 1.36 [0.89-1.53] m/s) and higher relative load at PWS (50.2 ± 14.4 and 51.7 ± 16.8 vs 36.2 ± 7.6 %V˙O₂peak and 101.9 ± 20.5 and 97.0 ± 27.3 vs 64.9 ± 13.8 %V˙O₂-VT). Energy cost at PWS of more impaired (0.30 [.19-1.03] mlO₂/kg/m) was higher than less-impaired (0.19[0.10-0.24] mlO₂/kg/m) and able-bodied (0.15 [0.13-0.18] mlO₂/kg/m). For post-stroke individuals, increasing walking speed above PWS decreased energy cost, but resulted in a relative load above endurance threshold.

SIGNIFICANCE

Individuals post-stroke seem to reduce walking speed to prevent unsustainably high relative aerobic loads at the expense of reduced economy. When aiming to improve walking ability post-stroke, it is important to consider training aerobic capacity.

Moderate-intensity exercise versus high-intensity interval training to recover walking post-stroke: protocol for a randomized controlled trial

Background

Stroke results in neurologic impairments and aerobic deconditioning that contribute to limited walking capacity which is a major barrier post-stroke. Current exercise recommendations and stroke rehabilitation guidelines recommend moderate-intensity aerobic training post-stroke. Locomotor high-intensity interval training is a promising new strategy that has shown significantly greater improvements in aerobic fitness and motor performance than moderate-intensity aerobic training in other populations. However, the relative benefits and risks of high-intensity interval training and moderate-intensity aerobic training remain poorly understood following stroke. In this study, we hypothesize that locomotor high-intensity interval training will result in greater improvements in walking capacity than moderate-intensity aerobic training.

Methods

Using a single-blind, 3-site randomized controlled trial, 50 chronic (> 6 months) stroke survivors are randomly assigned to complete 36 locomotor training sessions of either high-intensity interval training or moderate-intensity aerobic training. Main eligibility criteria are age 40–80 years, single stroke for which the participant received treatment (experienced 6 months to 5 years prior to consent), walking speed ≤ 1.0 m/s, able to walk at least 3 min on the treadmill at ≥ 0.13 m/s (0.3 mph), stable cardiovascular condition (American Heart Association class B), and the ability to walk 10 m overground without continuous physical assistance. The primary outcome (walking capacity) and secondary outcomes (self-selected and fast gait speed, aerobic fitness, and fatigue) are assessed prior to initiating training and after 4 weeks, 8 weeks, and 12 weeks of training.

Discussion

This study will provide fundamental new knowledge to inform the selection of intensity and duration dosing parameters for gait recovery and optimization of aerobic training interventions in chronic stroke. Data needed to justify and design a subsequent definitive trial will also be obtained. Thus, the results of this study will inform future stroke rehabilitation guidelines on how to optimally improve walking capacity following stroke.

Trial registration

ClinicalTrials.govNCT03760016. Registered on November 30, 2018.

Task-Oriented Circuit Training as an Alternative to Ergometer-Type Aerobic Exercise Training after Stroke

Moderate-intensity aerobic exercise training is an important treatment strategy to enhance functional recovery and decrease cardiometabolic risk factors after stroke. However, stroke related impairments limit access to ergometer-type exercise. The aims of the current study were (1) to evaluate whether our task-oriented circuit training protocol (intermittent functional training; IFT) could be used to sustain moderate-intensity aerobic workloads over a 10-week intervention period, and (2) to investigate its preliminary effects on cardiorespiratory fitness and metabolic profiles compared to constant-load ergometer-type exercise (CET). Forty chronic hemiparetic stroke survivors were randomized to receive 30 sessions of IFT or CET over ten weeks. Similar proportions of participants were randomized to IFT (7/19) and CET (9/18) sustained workloads associated with moderate-intensity aerobic exercise over the study period (p = 0.515). However, CET was associated with more substantial changes in maximal oxygen uptake (MD = 2.79 mL min⁻¹ kg⁻¹ CI: 0.84 to 4.74) compared to IFT (MD = 0.62 mL min⁻¹ kg⁻¹ CI: −0.38 to 1.62). Pre to post changes in C-reactive protein (−0.9 mg/L; p =0.017), short-term glycemia (+14.7 µmol/L; p = 0.026), and resting whole-body carbohydrate oxidation (+24.2 mg min⁻¹; p = 0.046) were observed when considering both groups together. Accordingly, IFT can replicate the aerobic intensities sustained during traditional ergometer-type exercise training. More work is needed to evaluate the dose–response effects of such task-oriented circuit training protocols on secondary prevention targets across the continuum of stroke recovery.

Novel velocity estimation for symmetric and asymmetric self-paced treadmill training

Background

Self-paced treadmills (SPT) can provide an engaging setting for gait rehabilitation by responding directly to the user’s intent to modulate the external environment and internal effort. They also can improve gait analyses by allowing scientists and clinicians to directly measure the effect of an intervention on walking velocity. Unfortunately, many common SPT algorithms are not suitable for individuals with gait impairment because they are designed for symmetric gait patterns. When the user’s gait is asymmetric due to paresis or if it contains large accelerations, the performance is diminished. Creating and validating an SPT that is suitable for asymmetric gait will improve our ability to study rehabilitation interventions in populations with gait impairment. The objective of this study was to test and validate a novel self-paced treadmill on both symmetric and asymmetric gait patterns and evaluate differences in gait kinematics, kinetics, and muscle activity between fixed-speed and self-paced treadmill walking.

Methods

We collected motion capture, ground reaction force data, and muscle activity from 6 muscles in the dominant leg during walking from 8 unimpaired subjects. In the baseline condition, the subjects walked at 3 fixed-speeds normalized to their leg length as Froude numbers. We developed a novel kinematic method for increasing the accuracy of the user’s estimated walking velocity and compared our method against other published algorithms at each speed. Afterward, subjects walked on the SPT while matching their walking speed to a given target velocity using visual feedback of the treadmill speed. We evaluated the SPT by measuring steady-state error and the number of steps to reach the desired speed. We split the gait cycle into 7 phases and compared the kinematic, kinetic, and muscle activity between the fixed speed and self-paced mode in each phase. Then, we validated the performance of the SPT for asymmetric gait by having subjects walk on the SPT while wearing a locked-knee brace set to 0° on the non-dominant leg.

Results

Our SPT enabled controlled walking for both symmetric and asymmetric gait patterns. Starting from rest, subjects were able to control the SPT to reach the targeted speeds using visual feedback in 13–21 steps. With the locked knee brace, subjects controlled the treadmill with substantial step length and step velocity asymmetry. One subject was able to execute a step-to gait and halt the treadmill on heel-strikes with the braced leg. Our kinematic correction for step-length outperformed the competing algorithms by significantly reducing the velocity estimation error at the tested velocities. The joint kinematics, joint torques, and muscle activity were generally similar between fixed-speed and self-paced walking. Statistically significant differences were found in 5 of 63 tests for joint kinematics, 2 of 63 tests for joint torques, and 9 of 126 tests for muscle activity. The differences that were statistically significant were not found across all speeds and were generally small enough to be of limited clinical relevance.

Conclusions

We present a validated method for implementing a self-paced treadmill for asymmetric and symmetric gaits. As a result of the increased accuracy of our estimation algorithm, our SPT produced controlled walking without including a position feedback controller, thereby reducing the influence of the controller on measurements of the user’s true walking speed. Our method relies only on a kinematic correction to step length and step time which can support transfer to systems outside of the laboratory for symmetric and asymmetric gaits in clinical populations.

The Value of High Intensity Locomotor Training Applied to Patients With Acute-Onset Neurologic Injury

Long-standing research in animal models and humans with stroke or incomplete spinal cord injury (iSCI) indicate that specific physical training variables, such as the specificity and amount of practice, may influence neurologic recovery and locomotor function. More recent data highlight the contributions of exercise intensity, as estimated indirectly by cardiovascular exertion, as potentially more important than previously considered. The effects of exercise intensity are well described in neurologically intact individuals, although confusion regarding the definitions of intensity and safety concerns have limited its implementation during physical rehabilitation of patients with neurologic injury. The purpose of this review is to delineate some of the evidence regarding the effects of exercise intensity during locomotor training in patients with stroke and iSCI. We provide specific definitions of exercise intensity used within the literature, describe methods used to ensure appropriate levels of exertion, and discuss potential adverse events and safety concerns during its application. Further details on the effects of locomotor training intensity on clinical outcomes, and on neuromuscular and cardiovascular function will be addressed as available. Existing literature across multiple studies and meta-analyses reveals that exercise training intensity is likely a major factor that can influence locomotor function after neurologic injury. To extend these findings, we describe previous attempts to implement moderate to high intensity interventions during physical rehabilitation of patients with neurologic injury, including the utility of specific strategies to facilitate implementation, and to navigate potential barriers that may arise during implementation efforts.

These legs were made for propulsion: advancing the diagnosis and treatment of post-stroke propulsion deficits

Advances in medical diagnosis and treatment have facilitated the emergence of precision medicine. In contrast, locomotor rehabilitation for individuals with acquired neuromotor injuries remains limited by the dearth of (i) diagnostic approaches that can identify the specific neuromuscular, biomechanical, and clinical deficits underlying impaired locomotion and (ii) evidence-based, targeted treatments. In particular, impaired propulsion by the paretic limb is a major contributor to walking-related disability after stroke; however, few interventions have been able to target deficits in propulsion effectively and in a manner that reduces walking disability. Indeed, the weakness and impaired control that is characteristic of post-stroke hemiparesis leads to heterogeneous deficits that impair paretic propulsion and contribute to a slow, metabolically-expensive, and unstable gait. Current rehabilitation paradigms emphasize the rapid attainment of walking independence, not the restoration of normal propulsion function. Although walking independence is an important goal for stroke survivors, independence achieved via compensatory strategies may prevent the recovery of propulsion needed for the fast, economical, and stable gait that is characteristic of healthy bipedal locomotion. We posit that post-stroke rehabilitation should aim to promote independent walking, in part, through the acquisition of enhanced propulsion. In this expert review, we present the biomechanical and functional consequences of post-stroke propulsion deficits, review advances in our understanding of the nature of post-stroke propulsion impairment, and discuss emerging diagnostic and treatment approaches that have the potential to facilitate new rehabilitation paradigms targeting propulsion restoration.

Implications of Physiology-Sensitive Gait Exercise on the Lower Limb Electromyographic Activity of Hemiplegic Post-Stroke Patients: A Feasibility Study in Low Resource Settings

Background: Stroke is one of the leading causes of disability with ~80% of post-stroke survivors suffering from gait-related deficits. Conventional gait rehabilitation settings are labor-intensive and need rigorous involvement of clinicians (who use their expertise to decide the dosage of exercise intensity based on patient’s capability). This demands a technology-assisted individualized exercise platform that can offer varying dosage of exercise intensity based on one’s capability. Here, we have used an individualized physiology-sensitive treadmill-assisted gait exercise platform. We wanted to investigate the implications of this platform on one’s lower limb muscle strength and muscle fatigue by analyzing surface Electromyogram (sEMG)-related indices and standard gait-related clinical measures. Methods: We designed a feasibility study involving post-stroke patients (n=9; 44.4(±15)years; post-stroke period=3.1(±3)years) and gave them multiple exposures to this exercise platform. We investigated the Gastrocnemius Lateralis and Tibialis Anterior muscle activation prior to and post multiple exposures to our exercise platform while they walked overground. The feasibility study ended with collecting feedback on the patients’ perception on the implications of having gait exercise using such a platform on their ambulation capability. Results: The results showed that repeated exposures to this gait exercise platform can contribute towards gait rehabilitation of post-stroke patients with rehabilitation outcomes measured in terms of group average improvement of (i)~14% in muscle strength and (ii)marginal (~6%) in functional mobility (as in our case). Conclusion: Such a physiology-sensitive treadmill-assisted gait exercise platform can hold promise towards contributing to post-stroke gait rehabilitation in low-resource settings with the rehabilitation outcomes being measured in terms of sEMG-based observations.

Recognizing Hemiparetic Ankle Deficits Using Wearable Pressure Sensors

Objective: To provide proof-of-concept for a novel method to recognize impaired push-off and foot-drop deficits in hemiparetic gait using analog pressure sensors. These data may enhance feedback from a modular ankle exoskeleton (such as Anklebot) for stroke rehabilitation, which now employs on/off foot switches under the foot. Methods: A pressure sensor was positioned on the posterior side of the calcaneus. Experiments were conducted on two healthy subjects with normal walking and with hip circumduction and foot drop, the latter to mimic hemiparetic gait post-stroke. Results: Unlike the foot switches, the pressure sensor yielded data during swing. The initial swing and terminal stance readings followed local foot-shoe dynamics and were thus able to detect foot drop swing deficits while also providing push-off information during stance. Discussion: The analog pressure sensors provided more information than foot switches, even during stance. This system may provide clinicians with a tool to monitor foot drop and push-off.

Augmented Performance Feedback during Robotic Gait Therapy Results in Moderate Intensity Cardiovascular Exercise in Subacute Stroke

BACKGROUND

Low cardiovascular fitness is common poststroke. Conventional subacute stroke rehabilitation does not meet Australian National Stroke Guidelines for cardiovascular exercise, particularly in mobility-dependent patients. Walking robotics can potentially achieve recommended cardiovascular exercise with these patients.

AIM

The primary aim was to determine whether sustained moderate intensity cardiovascular exercise can be achieved using 3 Lokomat Augmented Performance Feedback activities in mobility-dependent adults with subacute stroke. Secondary aims were to assess if cardiovascular workload was influenced by the activity completed, participants motivation or enjoyment, or changes in Lokomat settings.

METHODS

Ten patients with subacute stroke (mean (SD) age: 63.4 (13) years) participated in 6x20-minute Lokomat study sessions. Each study session involved a warm-up and 3x5-minute APF activities presented in a random order. Metabolic data were collected using the COSMED-K5. Participants rated their perceived exertion on the BORG CR10 scale and Lokomat settings of body-weight support, guidance force, and speed were recorded.

RESULTS

Moderate intensity cardiovascular exercise was achieved and maintained over the 15 minutes of exercise, objectively demonstrated by a mean (SD) Metabolic Equivalent Task of 3.1 (1.3), and mean (SD) oxygen consumption of 8.0 (3.8) ml/kg/min, estimated as 52% VO₂max. This was subjectively confirmed by exertion scores between 3 and 5. The cardiovascular workload was not affected by which activity was completed, participant motivation or enjoyment, or significant progression of Lokomat settings between study sessions.

CONCLUSIONS

Mobility-dependent patients with subacute stroke can achieve sustained moderate intensity cardiovascular exercise on the Lokomat when using APF activities.

Physical fitness training for stroke patients

BACKGROUND

Levels of physical activity and physical fitness are low after stroke. Interventions to increase physical fitness could reduce mortality and reduce disability through increased function.

OBJECTIVES

The primary objectives of this updated review were to determine whether fitness training after stroke reduces death, death or dependence, and disability. The secondary objectives were to determine the effects of training on adverse events, risk factors, physical fitness, mobility, physical function, health status and quality of life, mood, and cognitive function.

SEARCH METHODS

In July 2018 we searched the Cochrane Stroke Trials Register, CENTRAL, MEDLINE, Embase, CINAHL, SPORTDiscus, PsycINFO, and four additional databases. We also searched ongoing trials registers and conference proceedings, screened reference lists, and contacted experts in the field.

SELECTION CRITERIA

Randomised trials comparing either cardiorespiratory training or resistance training, or both (mixed training), with usual care, no intervention, or a non-exercise intervention in stroke survivors.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed quality and risk of bias, and extracted data. We analysed data using random-effects meta-analyses and assessed the quality of the evidence using the GRADE approach. Diverse outcome measures limited the intended analyses.

MAIN RESULTS

We included 75 studies, involving 3017 mostly ambulatory participants, which comprised cardiorespiratory (32 studies, 1631 participants), resistance (20 studies, 779 participants), and mixed training interventions (23 studies, 1207 participants). Death was not influenced by any intervention; risk differences were all 0.00 (low-certainty evidence). There were few deaths overall (19/3017 at end of intervention and 19/1469 at end of follow-up). None of the studies assessed death or dependence as a composite outcome. Disability scores were improved at end of intervention by cardiorespiratory training (standardised mean difference (SMD) 0.52, 95% CI 0.19 to 0.84; 8 studies, 462 participants; P = 0.002; moderate-certainty evidence) and mixed training (SMD 0.23, 95% CI 0.03 to 0.42; 9 studies, 604 participants; P = 0.02; low-certainty evidence). There were too few data to assess the effects of resistance training on disability. Secondary outcomes showed multiple benefits for physical fitness (VO2 peak and strength), mobility (walking speed) and physical function (balance). These physical effects tended to be intervention-specific with the evidence mostly low or moderate certainty. Risk factor data were limited or showed no effects apart from cardiorespiratory fitness (VO2 peak), which increased after cardiorespiratory training (mean difference (MD) 3.40 mL/kg/min, 95% CI 2.98 to 3.83; 9 studies, 438 participants; moderate-certainty evidence). There was no evidence of any serious adverse events. Lack of data prevents conclusions about effects of training on mood, quality of life, and cognition. Lack of data also meant benefits at follow-up (i.e. after training had stopped) were unclear but some mobility benefits did persist. Risk of bias varied across studies but imbalanced amounts of exposure in control and intervention groups was a common issue affecting many comparisons.

AUTHORS' CONCLUSIONS

Few deaths overall suggest exercise is a safe intervention but means we cannot determine whether exercise reduces mortality or the chance of death or dependency. Cardiorespiratory training and, to a lesser extent mixed training, reduce disability during or after usual stroke care; this could be mediated by improved mobility and balance. There is sufficient evidence to incorporate cardiorespiratory and mixed training, involving walking, within post-stroke rehabilitation programmes to improve fitness, balance and the speed and capacity of walking. The magnitude of VO2 peak increase after cardiorespiratory training has been suggested to reduce risk of stroke hospitalisation by ˜7%. Cognitive function is under-investigated despite being a key outcome of interest for patients. Further well-designed randomised trials are needed to determine the optimal exercise prescription, the range of benefits and any long-term benefits.

Effectiveness of treadmill training on gait function in children with cerebral palsy: meta-analysis

The purpose of this review was to analysis the effects of treadmill training on gait function in children with cerebral palsy. Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Central Register of Controlled Trials, Physiotherapy Evidence Database (PEDro), PubMed and Web of Science were searched. Investigating the effects of treadmill training on gait endurance, gait speed, limb support time, cadence, and step length in children with cerebral palsy. Similar outcomes were pooled by calculating the standardized mean difference. Of the eight studies, 179 participants were included. The average PEDro score was 6.25/10. The results of the sensitivity test for bias evaluation using the duval and tweedie's trim and fill method showed low publication bias. The test regarding the effect of treadmill training on overall gait function yielded a moderate effect size of 0.53, which was a statistically significant effect as its confidence interval did not include. The overall effect size of gait endurance was 0.85. The overall effect size of gait speed and limb support time were 0.52 and 0.73. The overall effect size of cadence and step length were 0.14 and 0.21, indicating a nonsignificant improvement. These findings suggested that treadmill training on cerebral palsy was effective for gait endurance, gait speed and limb support time than cadence and step length.

Reproducibility of Different Methodologies to Calculate Oxygen Consumption and Oxygen Cost During Walking in Chronic Stroke Survivors

OBJECTIVE

The most common methods to calculate energy costs are based on measured oxygen uptake during walking a standardized distance or time. Unfortunately, it is unclear which method is most reliable to determine energy cost of walking in stroke survivors. The objective of this study was to evaluate the 3 most commonly used methods for calculating oxygen consumption and -cost by assessing test-retest reliability and measurement error in community dwelling chronic stroke survivors during a 6 Minute Walk Test.

METHODS

In this secondary analysis of a longitudinal study, reproducibility of the outcome of walking distance, walking speed, oxygen consumption and oxygen cost from 3 methods (Kendall's tau, assumed steady-state and total walking time oxygen consumption) were determined using Intraclass Correlation Coefficient, Standard Error of Measurement and Smallest Detectable Change.

RESULTS

20 from the 31 participants successfully performed the 6 minute walk test-retest within a timeframe of 1 month. Within the 2 tests the reproducibility of walking distance and walking speed was high. The 3 methods to determine reproducibility for oxygen cost and oxygen consumption were considered good (Kendall's tau), good (assumed steady-state) and excellent (total walking time).

CONCLUSIONS

The method using oxygen consumption and -cost over the total walking time resulted in the highest reproducibility considering the Intraclass Correlation Coefficient, its 95% Confidence Interval, and smaller absolute differences.

Aerobic Exercise Recommendations to Optimize Best Practices in Care After Stroke: AEROBICS 2019 Update

Most stroke survivors have very low levels of cardiovascular fitness, which limits mobility and leads to further physical deconditioning, increased sedentary behavior, and heightened risk of recurrent stroke. Although clinical guidelines recommend that aerobic exercise be a part of routine stroke rehabilitation, clinical uptake has been suboptimal. In 2013, an international group of stroke rehabilitation experts developed a user-friendly set of recommendations to guide screening and prescription-the Aerobic Exercise Recommendations to Optimize Best Practices in Care after Stroke (AEROBICS 2013). The objective of this project was to update AEROBICS 2013 using the highest quality of evidence currently available. The first step was to conduct a comprehensive review of literature from 2012 to 2018 related to aerobic exercise poststroke. A working group of the original consensus panel members drafted revisions based on synthesis. An iterative process was used to achieve agreement among all panel members. Final revisions included: (1) addition of 115 new references to replace or augment those in the original AEROBICS document, (2) rewording of the original recommendations and supporting material, and (3) addition of 2 new recommendations regarding prescription. The quality of evidence from which these recommendations were derived ranged from low to high. The AEROBICS 2019 Update should make it easier for clinicians to screen for, and prescribe, aerobic exercise in stroke rehabilitation. Clinical implementation will not only help to narrow the gap between evidence and practice but also reduce current variability and uncertainty regarding the role of aerobic exercise in recovery after stroke.

WITHDRAWN: Immediate Adaptations to Poststroke Walking Performance Using a Wearable Robotic Exoskeleton

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Design and Evaluation of a Novel Experimental Setup for Upper Limb Intermuscular Coordination Studies

Motor disabilities limiting the mobility of limbs affect the quality of lives of people with neural injuries. Among various types of motor disabilities, abnormal intermuscular coordination is commonly observed from people with severe impairment. The concept of muscle synergy, defined as characteristic muscle co-activation patterns activated to produce complex motor behavior, has been applied to assess the alteration in intermuscular coordination in pathological populations. This study presents the development of a robotic system named KAIST upper limb synergy investigation system (KULSIS), for accurate measurement of intermuscular synergies while providing the convenient experimental setup. It provides full force/moment measurements for isometric force generation tasks at various upper limb postures and reaching tasks in a three-dimensional workspace. It is composed of: a three-degree-of-freedom gimbaled handle to adjust the orientation of the handle to accommodate potential hand-wrist deformity, a linear actuator that moves the handle for reaching tasks; a five-degree-of-freedom mechanism for positioning and adjusting the orientation of the linear actuator. The design was evaluated in terms of the workspace of the handle, mechanical stiffness and force/moment measurement accuracy. The position/force measurement is synchronized with electromyographic measurements. Muscle synergy patterns, activated during four isokinetic reaching motions, were also assessed as preliminary data using KULSIS from ten healthy subjects.

Preventing Muscle Atrophy Following Strokes: A Reappraisal

Muscle atrophy leading to muscle weakness accounts for major cause of disabilities among stroke survivors. It amounts to compromised gait and prevails to viscous cycle of diminished physical capacities and compromised participation in rehabilitative tasks. There is predisposition to recurrent strokes due to added risk of developing metabolic syndrome. Therefore, beyond the shadow of doubt, there is ripple effect of rehabilitation and thereby muscle protection in these subsets of patients. Herein, we highlight upon the newer insights with regard to preventing muscle atrophy following strokes.

What Is the Dose-Response Relationship Between Exercise and Cardiorespiratory Fitness After Stroke? A Systematic Review

BACKGROUND

Exercise after stroke improves cardiorespiratory fitness and walking capacity; however, the effect of altering exercise dose (via frequency, intensity, time, and type) on fitness or walking capacity is unclear.

PURPOSE

The purpose of this study was to synthesize the current evidence for the effects of different doses of exercise on cardiorespiratory fitness and walking capacity in people after stroke.

DATA SOURCES

Seven relevant electronic databases were searched using keywords relating to stroke and cardiorespiratory fitness.

STUDY SELECTION

Trials that compared more than 1 dose of exercise for people (≥ 18 years old) after stroke and measured peak oxygen consumption or 6-minute walk test distance as an outcome were included. Two reviewers independently appraised all trials.

DATA EXTRACTION

Two reviewers independently extracted data from included articles. Intervention variables were extracted in accordance with the Template for Intervention Description and Replication checklist.

DATA SYNTHESIS

Data were synthesized narratively. Nine trials involving 279 participants were included. Three of 5 trials comparing exercise intensity showed that higher-intensity training was associated with greater improvements in cardiorespiratory fitness. The effects of other exercise dose components (frequency, time, and type) on fitness were not determined. Overall, walking capacity improved as program length increased.

LIMITATIONS

All trials had a high risk of bias, and most had a high rate of attrition. Most trials included people more than 6 months after stroke and who walked independently, limiting the generalizability of the findings.

CONCLUSIONS

Exercising at an intensity greater than 70% of heart rate reserve can be more effective in increasing cardiorespiratory fitness after stroke than exercising at lower intensities. More trials that compare exercise doses by manipulating only 1 dose parameter at a time for people after stroke are needed.

Progressive Respiratory Muscle Training for Improving Trunk Stability in Chronic Stroke Survivors: A Pilot Randomized Controlled Trial

BACKGROUND

Stroke weakens the respiratory muscles, which in turn may influence the trunk stability; it is unclear whether the progressive respiratory muscle training (RMT) is effective in improving the trunk stability. The aim of this study was to investigate the effects of progressive RMT with trunk stabilization exercise (TSE) on respiratory muscles thickness, respiratory muscle functions, and trunk stability in chronic stroke survivors.

METHODS

This is a pilot randomized controlled trial. Chronic stroke survivors (n = 33) who were able to sit independently participated in the tstudy. The participants were allocated into the RMP with TSE group or the TSE group. The respiratory muscle thickness during resting and contraction were measured. Maximal expiratory pressure (MEP), peak expiratory flow (PEF), and forceful expiratory volume at 1 sec (FEV1) for forced expiratory muscle function and maximal inspiratory pressure (MIP), peak inspiratory flow (PIF), and vital capacity (VC) for inspiratory muscle function were examined. Trunk stability was estimated by maximal velocity and path length of the center of pressure (COP) by using a balance board with sitting posture.

RESULTS

The respiratory muscle thickness was significantly increased on the affected side in the RMT group than in the TSE group. The MEP, PEF, MIP, and PIF were significantly increased in the RMT group than in the TSE group; however, FEV1 and VC showed no significant differences between the 2 groups. Trunk stability for the maximal velocity of COP of extension and affected side bending was significantly increased in the RMT group than in the TSE group. In addition, the maximal path length of COP of flexion, extension, affected/less affected side bending was significantly increased in the RMT group than in the TSE group.

CONCLUSIONS

RMT combined with TSE can be suggested as an effective method to improve the respiratory muscle thickness, respiratory muscle functions, and trunk stability in chronic stroke survivors as opposed to TSE only.

Decreased Respiratory Muscle Function Is Associated with Impaired Trunk Balance among Chronic Stroke Patients: A Cross-sectional Study

The abdominal muscles play a role in trunk balance. Abdominal muscle thickness is asymmetrical in stroke survivors, who also have decreased respiratory muscle function. We compared the thickness of the abdominal muscles between the affected and less affected sides in stroke survivors. In addition, the relationship between respiratory muscle function and trunk balance was evaluated. Chronic stroke patients (18 men, 15 women; mean age, 58.94 ± 12.30 years; Mini-Mental Status Examination score ≥ 24) who could sit without assist were enrolled. Abdominal muscle thickness during rest and contraction was measured with ultrasonography, and the thickening ratio was calculated. Respiratory muscle function assessment included maximum respiratory pressure, peak flow, and air volume. Trunk function was evaluated using the Trunk Impairment Scale, and trunk balance was estimated based on the center of pressure velocity and path length within the limit of stability in sitting posture. Abdominal muscles were significantly thinner on the affected side, and the thickening ratio was lower in the affected side (P < 0.05). In addition, the higher thickening ratio of the affected side showed significant relationship with higher trunk function. Moreover, higher respiratory muscle function was significantly correlated with higher level of trunk function and balance in stroke patients (P < 0.05). Thus, chronic stroke survivors have decreased abdominal muscle thickness on the affected side, and respiratory muscle function has positive correlation with trunk function and balance. We propose that respiratory muscle training should be included as part of trunk balance training in chronic stroke patients.

A planar neuro-musculoskeletal arm model in post-stroke patients

Mathematical modeling of the neuro-musculoskeletal system in healthy subjects has been pursued extensively. In post-stroke patients, however, such models are very primitive. Besides improving our general understanding of how stroke affects the limb motions, they can be used to evaluate rehabilitation strategies by computer simulations before clinical evaluations. A planar neuro-musculoskeletal arm model for post-stroke patients is developed. The main idea is to use a set of new coefficients, Muscle Significance Factors (MSF), to incorporate the effects of stroke in the muscle control performance. The model uses the optimal control theory to mimic the performance of the CNS and a two-link skeletal model with six muscles for the biomechanical part. The model was developed and evaluated using experimental data from six post-stroke patients with Brunnstrom levels of 4-6. The results show that MSFs are relatively distinct and independent from the arm motion which is used to determine their values. Its variation is in the range of 0-2.58% and decreases in higher Brunnstrom levels. The mean error of the model in predicting the path of motion varies from 0.9% in level 6 to 5.58% in level 4 subjects which can be considered a promising level of accuracy. Using the proposed model and the MSF to customize the model for each individual stroke patient seems a promising approach. It shows a reasonable level of robustness, i.e., independence from the type of motions and correlated with the severity of stroke, and accuracy in predicting the shape of the motion path.

Effect of Gravity and Task Specific Training of Elbow Extensors on Upper Extremity Function after Stroke

BACKGROUND

In individuals with hemiparetic stroke, reaching with the paretic arm can be impaired by abnormal muscle coactivation. Prior trails for improving upper extremity functions after stroke have underestimated the role of gravitational force in motor planning and execution.

OBJECTIVE

The aims this trial were to study the effect of gravity as a facilitator for elbow extension and to estimate the immediate and retention effects of task specific training of elbow extensors on upper extremity function after stroke.

METHODS

Twenty-six right handed patients with first ever stroke represented the sample of the study. The participants were randomly assigned into two equal groups. The study group received treatment through two phases. Phase one included training for the elbow extensors in an antigravity position. Phase two included a set of task specific exercise for 16 weeks. The control group received traditional passive stretch and range of motion exercises. Manual dexterity and upper limb function were assessed by Nine-Hole Peg Test and Fugl-Meyer upper extremity. Goniometry was used for measuring elbow extension and forearm supination active ranges of motion.

RESULTS

Significant improvements were observed in Nine-Hole Peg Test, Fugl-Meyer upper extremity, and ranges of motion at postintervention and follow-up compared to preintervention at P≤0.05.

CONCLUSIONS

The results of this study provide an evidence that antigravity positions can be used as a centrally presented facilitator of elbow extension. Additionally, task specific training was effective in improving upper extremity function and elbow extension range of motion.

Physical fitness interventions for nonambulatory stroke survivors: A mixed-methods systematic review and meta-analysis

INTRODUCTION

Physical fitness training after stroke is recommended in guidelines across the world, but evidence pertains mainly to ambulatory stroke survivors. Nonambulatory stroke survivors (FAC score ≤2) are at increased risk of recurrent stroke due to limited physical activity. This systematic review aimed to synthesize evidence regarding case fatality, effects, experiences, and feasibility of fitness training for nonambulatory stroke survivors.

METHODS

Eight major databases were searched for any type of study design. Two independent reviewers selected studies, extracted data, and assessed study quality, using published tools. Random-effects meta-analysis was used. Following their separate analysis, qualitative and quantitative data were synthesized using a published framework.

RESULTS

Of 13,614 records, 33 studies involving 910 nonambulatory participants met inclusion criteria. Most studies were of moderate quality. Interventions comprised assisted walking (25 studies), cycle ergometer training (5 studies), and other training (3 studies), mainly in acute settings. Case fatality did not differ between intervention (1.75%) and control (0.88%) groups (95% CI 0.13-3.78, p = 0.67). Compared with control interventions, assisted walking significantly improved: fat mass, peak heart rate, peak oxygen uptake and walking endurance, maximum walking speed, and mobility at intervention end, and walking endurance, balance, mobility, and independent walking at follow-up. Cycle ergometry significantly improved peak heart rate, work load, peak ventilation, peak carbon dioxide production, HDL cholesterol, fasting insulin and fasting glucose, and independence at intervention end. Effectiveness of other training could not be established. There were insufficient qualitative data to draw conclusions about participants' experiences, but those reported were positive. There were few intervention-related adverse events, and dropout rate ranged from 12 to 20%.

CONCLUSIONS

Findings suggest safety, effectiveness, and feasibility of adapted fitness training for screened nonambulatory stroke survivors. Further research needs to investigate the clinical and cost-effectiveness as well as experiences of fitness training-especially for chronic stroke survivors in community settings.

Rhythmic arm swing integrated into treadmill training in patients with chronic stroke: A single-subject experimental study

Normal walking includes coordinated and controlled movement of the legs and arms. However, patients following stroke often present with inappropriate motor control which limits coordinated movement patterns of the affected limbs. This study aimed to compare the effects of rhythmic arm swing and arm fixation during treadmill walking in patients with poststroke hemiparesis. We used an alternating study design with multiple baselines across subjects. Three patients with chronic stroke participated in this study. During treadmill walking, rhythmic arm swing and arm fixation conditions were alternately applied. Outcome measures included the 10-meter walk test (10MWT) and energy expenditure index (EEI). In the intervention phase, all subjects showed significantly greater improvements in the 10MWT and EEI scores for rhythmic arm swing condition compared to those for arm fixation condition (p < 0.05). 10MWT improvement rates: Subject 1-34.81% vs. 15.75%; Subject 2-40.00% vs. 17.95%; and Subject 3-38.08% vs. 21.85%; and EEI improvements: Subject 1-23.19% vs. 14.08%; Subject 2-26.15% vs. 20.43%; and Subject 3-22.99% vs. 14.49%. These findings suggest that rhythmic arm swing is clinically feasible as a more favorable option to enhance the effects of treadmill walking training. However, larger studies with a different study design are needed to be able to make any judgment about the usefulness of the treatment.

Effects of combined endurance and resistance training in Amyotrophic Lateral Sclerosis: A pilot, randomized, controlled study

Based on available evidence, muscle strengthening and cardiovascular exercises can help maintain function and not adversely affect the progression of disease in patients with ALS. However, this evidence is not sufficiently detailed to recommend a specific exercise prescription. The purpose of this project was to assess clinical outcomes of a combined exercise programme to increase knowledge of rehabilitation in ALS patients. 38 ALS patients were assigned randomly to two groups: one group underwent a specific exercise programme (ALS-EP) based on a moderate aerobic workout and isometric contractions, and the second group followed a standard neuromotor rehabilitation treatment. Objective evaluation consisted of cardiovascular measures, muscle strength and fatigue. Some positive effects of physical activity on ALS patients were found. Among the benefits, an overall improvement of functional independence in all patients, independently of the type of exercise conducted was seen. In addition, improvements in muscle power, oxygen consumption and fatigue were specifically observed in the ALS-EP group, all hallmarks of a training effect for the specific exercises. In conclusion, moderate intensity exercise is beneficial in ALS, helping in avoiding deconditioning and muscle atrophy resulting from progressive inactivity.

Four birds with one stone? Reparative, neuroplastic, cardiorespiratory, and metabolic benefits of aerobic exercise poststroke

PURPOSE OF REVIEW

Converging evidence from animal models of stroke and clinical trials suggests that aerobic exercise has effects across multiple targets.

RECENT FINDINGS

The subacute phase is characterized by a period of heightened neuroplasticity when aerobic exercise has the potential to optimize recovery. In animals, low intensity aerobic exercise shrinks lesion size and reduces cell death and inflammation, beginning 24 h poststroke. Also in animals, aerobic exercise upregulates brain-derived neurotrophic factor near the lesion and improves learning. In terms of neuroplastic effects, clinical trial results are less convincing and have only examined effects in chronic stroke. Stroke patients demonstrate cardiorespiratory fitness levels below the threshold required to carry out daily activities. This may contribute to a 'neurorehabilitation ceiling' that limits capacity to practice at a high enough frequency and intensity to promote recovery. Aerobic exercise when delivered 2-5 days per week at moderate to high intensity beginning as early as 5 days poststroke improves cardiorespiratory fitness, dyslipidemia, and glucose tolerance.

SUMMARY

Based on the evidence discussed and applying principles of periodization commonly used to prepare athletes for competition, we have created a model of aerobic training in subacute stroke in which training is delivered in density blocks (duration × intensity) matched to recovery phases.

Comparison of Resistance-Based Walking Cardiorespiratory Test to the Bruce Protocol

Hurt, CP, Bamman, M, Naidu, A, and Brown, DA. Comparison of resistance-based walking cardiorespiratory test to the Bruce Protocol. J Strength Cond Res 34(12): 3569-3576, 2020-Cardiorespiratory fitness is assessed through graded exercise tests that determine the maximum amount of sustained mechanical work that an individual can perform while also providing health- and fitness-related information. This article describes a novel method to perform graded exercise tests that use posteriorly directed resistive forces. The purpose of this investigation was to validate a novel resistance-based test (RBT) in comparison with a traditional speed- and incline-based test (SIBT) in a cohort of nonimpaired individuals. Twenty nonimpaired individuals, 8 men and 20 women age 28.4 ± 9.6, range 20-54 years old performed 2 maximal exercise tests. The SIBT used the Bruce Protocol and increased treadmill incline and speed every 3 minutes. The RBT used a robotic device interfaced with the treadmill that provided specified horizontal resistive forces at the center of mass calculated to match each Bruce Protocol stage while individuals walked at 1.1 m·s. Subjects obtained ∼3% higher maximum V[Combining Dot Above]O2 measure using the speed- and incline-based method (dependent t-test p = 0.08). V[Combining Dot Above]O2peaks between tests were strongly correlated (r = 0.93, p < 0.001). Peak values of secondary physiologic measures (i.e., max heart rate and respiratory exchange ratio) were within 3% between tests. We found a significant linear relationship between mass-specific work rate and measured V[Combining Dot Above]O2 stage by stage for both tests, but no significant difference between each linear fit (p = 0.84). These data suggest that horizontal resistive forces, while walking on a treadmill, can be used to increase aerobic effort in a way that closely simulates work rates of the Bruce Protocol.

Increased Energy Cost of Mobility in Chronic Stroke

The purpose of this study was to compare the energy cost of completing mobility-related activities in chronic stroke to the estimated energy cost found in the compendium of physical activities, a resource that estimates and classifies energy cost of various human physical activities. Men (n=18) and women (n=10) with chronic hemiparetic gait (stroke latency: 4 ± 2 years, age: 60.4 ± 1.6 years, BMI: 31.5 ± 1.1 kg/m²) participated in the study. Portable energy cost monitoring (COSMED K4b2) was performed during five mobility activities of varying intensity to determine metabolic equivalents (METs, or oxygen consumption in multiples of resting level) for each activity. The METs achieved during the five activities were compared to the following compendium MET values for: 1) floor sweeping; 2) stepping in place; 3) over-ground walking; 4) lower speed treadmill walking (1.0 mph at 4% incline); and 5) higher speed treadmill walking (2.0 mph at 4% incline). Measurements were obtained for 10 min at rest and 5 minutes during each of the five activities. The energy cost of rest was only 85% of Compendium METS, while mobility-related activities were ~1.25-1.50 fold greater when measured in stroke vs. Compendium METS for all measures (P's<0.05), except floor sweeping, which was similar between groups. These data indicate that MET levels provided in the compendium are not applicable to chronic stroke survivors as they overestimate energy expenditure at rest and underestimate energy expenditure during physical activity, indicating poor efficiency in movement, thus elevating the oxygen cost of completing general daily activities.

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).

Diaphragm Thickness and Inspiratory Muscle Functions in Chronic Stroke Patients

Background

The aims of this study are to investigate the difference between the diaphragm thickness at end expiration and the thickness at total lung capacity (TLC), and to examine differences in inspiratory muscle function between stroke patients and healthy individuals.

Material/Methods

Forty-five stroke patients and 49 healthy volunteers were included in this study. Diaphragm thickness was measured at end expiration and at TLC by ultrasonography. The maximal inspiratory pressure (MIP), peak inspiratory flow (PIF), vital capacity (VC), and inspiratory muscle endurance (IME) were assess to evaluate inspiratory muscle function.

Results

In stroke patients, the diaphragm was significantly thinner on the affected side than the less affected side at end expiration and at TLC. The change between the thickness at end expiration and at TLC were also significant on both sides. Between groups, the difference in diaphragm thickness at end expiration was not significant, but at TLC, the diaphragms were significantly thicker in healthy individuals than on either side in stroke patients, and the change in diaphragm thickness was significantly greater for healthy individuals. Inspiratory muscle functions were also significantly greater in healthy individuals. MIP, PIF, and VC were positively correlated with the change in thickness in healthy individuals, and MIP was positively correlated with the change in thickness and IME in stroke patients.

Conclusions

Stroke patients showed decreases in the thickening ability of the diaphragm at TLC and in inspiratory muscle function. The change between the diaphragm thickness at end expiration and at TLC was positively correlated with MIP, PIF, and VC.

180° turn while walking: characterization and comparisons between subjects with and without stroke

[Purpose] Limitations in performing the 180°-turning increase the risk of falls and disabilities in stroke patients. The aim of this study was to characterize and compare the 180°-turning between people with and without stroke, considering the direction towards which they turned. [Subjects and Methods] Fourteen subjects with stroke and 14 matched healthy controls performed the 180°-turning twice while walking: towards the self-selected, and the opposite directions. The turning performances were recorded using three video cameras. The videos were randomly analyzed by a single examiner, who characterized the turning, while considering the time required to complete the task, the number of steps, balance, and turning type. Friedman Tests and ANOVA (2 × 2) were used to compare the groups and turning direction factors (turning towards the self-selected versus opposite sides, and towards the paretic/non-dominant versus non-paretic/dominant sides). [Results] No interaction between the groups and turning directions, and no significant differences between the turning directions were found. However, significant differences were found between the groups for all variables used to characterize the turning performance, except for the type of turning. [Conclusion] Stroke subjects demonstrated poor performance on the 180°-turning, regardless of the turning direction. Duration, number of steps, and balance loss indicated difficulties in turn performance.

Action observation training of community ambulation for improving walking ability of patients with post-stroke hemiparesis: a randomized controlled pilot trial

Purpose:

To investigate the effects of action observation training involving community-based ambulation for improving walking ability after stroke.

Design:

Randomized, controlled pilot study.

Setting:

Inpatient rehabilitation hospital.

Subjects:

A total of 25 inpatients with post-stroke hemiparesis were randomly assigned to either the experimental group ( n = 12) or control group ( n = 13).

Intervention:

Subjects of the experimental group watched video clips demonstrating four-staged ambulation training with a more complex environment factor for 30 minutes, three times a week for four weeks. Meanwhile, subjects of the control group watched video clips, which showed different landscape pictures.

Main measures:

Walking function was evaluated before and after the four-week intervention using a 10-m walk test, community walk test, activities-specific balance confidence scale, and spatiotemporal gait measures.

Results:

Changes in the values for the 10-m walk test (0.17 ±0.19 m/s vs. 0.05 ±0.08 m/s), community walk test (–151.42 ±123.82 seconds vs. 67.08 ±176.77 seconds), and activities-specific balance confidence (6.25 ±5.61 scores vs. 0.72 ±2.24 scores) and the spatiotemporal parameters (i.e. stride length (19.00 ±11.34 cm vs. 3.16 ±11.20 cm), single support (5.87 ±5.13% vs. 0.25 ±5.95%), and velocity (15.66 ±12.34 cm/s vs. 2.96 ±10.54 cm/s)) indicated a significant improvement in the experimental group compared with the control group. In the experimental group, walking function and ambulation confidence was significantly different between the pre- and post-intervention, whereas the control group showed a significant difference only in the 10-m walk test.

Conclusions:

Action observation training of community ambulation may be favorably used for improving walking function of patients with post-stroke hemiparesis.

Can aerobic treadmill training reduce the effort of walking and fatigue in people with multiple sclerosis: a pilot study

Impaired mobility in multiple sclerosis (MS) is associated with high-energy costs and effort when walking, gait abnormalities, poor endurance and fatigue. This repeated measures trial with blinded assessments investigated the effect of treadmill walking at an aerobic training intensity in 16 adults with MS. The intervention consisted of 12 sessions of up to 30 minutes treadmill training (TT), at 55–85% of age-predicted maximum heart rate. The primary outcome measure was walking effort, measured by oxygen consumption (mL/kg per metre), during treadmill walking at comfortable walking speed (CWS). Associated changes in gait parameters using the ‘Gait-Rite’ mat, 10-m time and 2-minute distance, and Fatigue Severity Scale were examined. Following training, oxygen consumption decreased at rest (P = 0.008), CWS increased (P = 0.002), and 10-m times (P = 0.032) and walking endurance (P = 0.020) increased. At increased CWS, oxygen consumption decreased (P = 0.020), with a decreased time spent in stance in the weaker leg (P = 0.034), and a greater stride distance with the stronger leg (P = 0.044). Reported fatigue levels remained the same. Aerobic TT presents the opportunity to alter a motor skill and reduce the effort of walking, whilst addressing cardiovascular de-conditioning, thereby, potentially reducing effort and fatigue for some people with MS.

Coordination of Hemiparetic Locomotion after Stroke Rehabilitation

Objectives. Determine whether a rehabilitation program targeting functional motor recovery of persons with poststroke hemiparesis improved motor coordination. Methods. A subgroup of 20 persons with poststroke hemiparesis (n = 11 in intervention and n =9incontrol group) was investigated from within a larger randomized controlled single-blind clinical trial of 100 patients. Motor coordination was measured using a pedaling task, and subjects in the intervention group pedaled during an intensive broad-based home exercise program that targeted flexibility, strength, balance, and endurance. Coordination variables based on paretic leg pedal forces and EMG of 4 thigh muscles were measured while pedaling pre- and postintervention. Results. Despite extensive pedaling practice, up to 30 half-hour sessions that were progressively more intense, there was no effect (P > 0.05) of the intervention on percent of total work done by the paretic leg, quantitative measures of EMG, or pedaling speed. However, walking speed was improved and pedaling and walking faster were associated after the intervention. Conclusions. There is no evidence of improved locomotor coordination postintervention. The increased walking and pedaling speed was likely achieved by a more proficient use of the same impaired pattern without EMG timing changes, likely because of increased strength and endurance postintervention. A more task-specific intervention may be required to improve coordination, consistent with principles of use-dependent plasticity.