Energy Cost During the 6-Minute Walk Test and Its Relationship to Real-World Walking After Stroke: A Correlational, Cross-Sectional Pilot Study

Measurement properties of activity monitoring for a rehabilitation (AMoR) platform in post-stroke individuals in a simulated home environment

AIM

The aim of this study was to evaluate the measurement properties of activity monitoring for a rehabilitation (AMoR) platform for step counting, time spent in sedentary behavior, and postural changes during activities of daily living (ADLs) in a simulated home environment.

METHODS

Twenty-one individuals in the post-stroke chronic phase used the AMoR platform during an ADL protocol and were monitored by a video camera. Spearman's correlation coefficient, mean absolute percent error (MAPE), intraclass correlation coefficient (ICC), and Bland-Altman plot analyses were used to estimate the validity and reliability between the AMoR platform and the video for step counting, time spent sitting/lying, and postural changes from sit-to-stand (SI-ST) and sit-to-stand (ST-SI).

RESULTS

Validity of the platform was observed with very high correlation values for step counting (rs = 0.998) and time spent sitting/lying (rs = 0.992) and high correlation for postural change of SI-ST (rs = 0.850) and ST-SI (rs = 0.851) when compared to the video. An error percentage above 5% was observed only for the SI-ST postural change (7.13%). The ICC values show excellent agreement for step counting (ICC3, k = 0.999) and time spent sitting/lying (ICC3, k = 0.992), and good agreement for SI-ST (ICC3, k = 0.859) and ST-SI (ICC3, k = 0.936) postural change. Values of the differences for step counting, sitting/lying time, and postural change were within the limits of agreement according to the analysis of the Bland-Altman graph.

CONCLUSION

The AMoR platform presented validity and reliability for step counting, time spent sitting/lying, and identification of SI-ST and ST-SI postural changes during tests in a simulated environment in post-stroke individuals.

Interventions to Change Movement Behaviors After Stroke: A Systematic Review and Meta-analysis

OBJECTIVE

This systematic review aimed to determine which interventions increase physical activity (PA) and decrease sedentary behavior (SB) based on objective measures of movement behavior in individuals with stroke.

DATA SOURCES

The PubMed (Medline), EMBASE, Scopus, CINAHL (EBSCO), and Web of Science databases were searched for articles published up to January 3, 2023.

STUDY SELECTION

The StArt 3.0.3 BETA software was used to screen titles, abstracts, and full texts for studies with randomized controlled trial designs; individuals with stroke (≥18 years of age); interventions aimed at increasing PA or decreasing SB; and objective measurement instruments.

DATA EXTRACTION

Data extraction was standardized, considering participants and assessments of interest. The risk of bias and quality of evidence of the included studies were assessed.

DATA SYNTHESIS

Twenty-eight studies involving 1855 patients were included. Meta-analyses revealed that in the post-stroke acute/subacute phase, exercise interventions combined with behavior change techniques (BCTs) increased both daily steps (standardized mean difference [SMD]=0.65, P=.0002) and time spent on moderate-to-vigorous intensity physical activities (MVPAs) duration of PA (SMD=0.68, P=.0004) with moderate-quality evidence. In addition, interventions based only on BCTs increased PA levels with very low-quality evidence (SMD (low-intensity physical activity)=0.36, P=.02; SMD (MVPA)=0.56, P=.0004) and decreased SB with low-quality evidence (SMD=0.48, P=.03). In the post-stroke chronic phase, there is statistical significance in favor of exercise-only interventions in PA frequency (steps/day) with moderate-quality evidence (SMD=0.68, P=.002). In general, the risk of bias in the included studies was low.

CONCLUSIONS

In the acute/subacute phase after stroke, the use of BCTs combined with exercise can increase the number of daily steps and time spent on MVPA. In contrast, in the post-stroke chronic phase, exercise-only interventions resulted in a significant increase in daily steps.

Treatment of knee hyperextension in post-stroke gait. A systematic review

BACKGROUND

Post-stroke, patients exhibit considerable variations in gait patterns. One of the variations that can be present in post-stroke gait is knee hyperextension in the stance phase.

RESEARCH QUESTION

What is the current evidence for the effectiveness of the treatment of knee hyperextension in post-stroke gait?

METHODS

MEDLINE, EMBASE, PEDro, CINAHL, and the Cochrane library were searched for relevant controlled trials. Two researchers independently extracted the data and assessed the methological quality. A best evidence synthesis was conducted to summarize the results.

RESULTS

Eight controlled trials (5 RCTs, 3 CCTs) were included. Three types of interventions were identified: proprioceptive training, orthotic treatment, and functional electrostimulation (FES). In the included studies, the time since the stroke occurrence varied from the (sub)acute phase to the chronic phase. Only short-term effects were investigated. The adjustment from a form of proprioceptive training to physiotherapy training programs seems to be effective (moderate evidence) for treating knee hyperextension in gait, as applied in the subacute phase post-stroke. Neither evidence for effects on gait speed nor gait symmetry were found as a result of proprioceptive training. Orthoses that cover the knee have some effects (limited evidence) on knee hyperextension and gait speed. No evidence was found for FES.

SIGNIFICANCE

This is the first systematic literature review on the effectiveness of interventions on knee hyperextension in post-stroke gait. We found promising results (moderate evidence) for some "proprioceptive approaches" as an add-on therapy to physiotherapy training programs for treating knee hyperextension during the subacute phase post-stroke, in the short-term. Therefore, initially, clinicians should implement a training program with a proprioceptive approach in order to restore knee control in these patients. Because only studies reporting short-term results were found, more high-quality RCTs and CCTs are needed that also study mid- and long-term effects.

Serum activity of matrix metalloproteinase-2 and -9 is increased in chronic post-stroke individuals: a cross-sectional exploratory study

BACKGROUND

High concentrations of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) are associated with inflammation early after stroke. In chronic stages, the elevation of some cytokines is related to the presence of co-morbid conditions in these individuals. In addition to this, some characteristics such as sensorimotor impairment, atrophy, and sedentary lifestyle predispose the system to an inflammatory response.

OBJECTIVE

To quantify MMP-2 and -9 serum activity in chronic post-stroke individuals and correlate it with variables of physical activity level, body composition, functional and walking capacity, and with inflammatory biomarkers. Additionally, gelatinase activity was characterized according to motor impairment.

METHODS

Fourteen patients with stroke onset >6 months and seven healthy individuals were enrolled in this study. The clinical assessment included: body composition, measure by bioelectrical impedance analyzer; Fugl-Meyer Motor Assessment Scale; six-minute and ten-meter walk tests, and physical activity level assessed by the StepWatch® Activity Monitor. Blood samples were collected from antecubital vein and serum MMP-2 and -9 activity was analyzed using gelatin Zymography, and the TNFα, IL-6, IL-1β, IL-10 biomarkers using ELISA kits.

RESULTS

Chronic post-stroke individuals presented an increased activity of MMP-2 and -9 compared to healthy individuals. Positive correlations with time and steps in low cadence and negative ones with medium cadence and peak activity index were observed. According to the motor impairment, the MMP-2 activity was increased in the mild-moderate group compared to the control group.

CONCLUSION

Increased gelatinases in chronic post-stroke individuals could describe an inflammation process related to the limited capacity of walking in high intensities.

Integrating Survivors of Stroke Into Exercise-Based Cardiac Rehabilitation Improves Endurance and Functional Strength

Background

Cardiac rehabilitation (CR) is a structured exercise program prevalent in the United States for people with cardiovascular disease that has been shown to increase cardiovascular endurance and improve quality of life. Despite similar cardiovascular risk factors, stroke is not among the covered diagnoses for CR. The purpose of this study was to examine the participant impact of integrating survivors of stroke into the exercise portion of an existing hospital‐based CR program through measures of physical function and other health impacts and through qualitative evaluation of participant perception.

Methods and Results

Subacute and chronic survivors of stroke were integrated into a standard 12‐week, 3 sessions per week, exercise‐based CR program. A total of 29 began the program, 24 completed the program, and 18 were available for 6‐month follow‐up. Quantitative measures were compared preprogram with postprogram with t‐test or equivalent, and preprogram with postprogram to 6‐month follow‐up with ANOVA or equivalent. Semistructured interviews were completed with 11 participants postprogram. Exercise‐based CR had significant impacts on cardiovascular endurance preprogram to postprogram, with maintenance at 6‐month follow‐up. The participants improved on the 6‐minute walk test on average by 61.92 m(95% CI, 33.99–89.84 m), and maximum metabolic equivalents improved by a median of 3.6 (interquartile range, 2.35). Five times sit to stand (functional strength) improved preprogram to postprogram by a median of 2.85 s (interquartile range, 4.03 s). Qualitative findings highlight additional health improvements. Most participants (83% [15/18]) reported continued exercise at follow‐up.

Conclusions

Exercise‐based CR has the potential to improve cardiovascular endurance, health status, and quality of life for survivors of stroke.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03706105.

Underlying mechanisms of oxygen uptake kinetics in chronic post-stroke individuals: A correlational, cross-sectional pilot study

Post-stroke individuals presented deleterious changes in skeletal muscle and in the cardiovascular system, which are related to reduced oxygen uptake ([Formula: see text]) and take longer to produce energy from oxygen-dependent sources at the onset of exercise (mean response time, MTRON) and during post-exercise recovery (MRTOFF). However, to the best of our knowledge, no previous study has investigated the potential mechanisms related to [Formula: see text] kinetics response (MRTON and MRTOFF) in post-stroke populations. The main objective of this study was to determine whether the MTRON and MRTOFF are related to: 1) body composition; 2) arterial compliance; 3) endothelial function; and 4) hematological and inflammatory profiles in chronic post-stroke individuals. Data on oxygen uptake ([Formula: see text]) were collected using a portable metabolic system (Oxycon Mobile®) during the six-minute walk test (6MWT). The time to achieve 63% of [Formula: see text] during a steady state (MTRON) and recovery (MRTOFF) were analyzed by the monoexponential model and corrected by a work rate (wMRTON and wMRTOFF) during 6MWT. Correlation analyses were made using Spearman's rank correlation coefficient (rs) and the bias-corrected and accelerated bootstrap method was used to estimate the 95% confidence intervals. Twenty-four post-stroke participants who were physically inactive took part in the study. The wMRTOFF was correlated with the following: skeletal muscle mass (rs = -0.46), skeletal muscle mass index (rs = -0.45), augmentation index (rs = 0.44), augmentation index normalized to a heart rate of 75 bpm (rs = 0.64), reflection magnitude (rs = 0.43), erythrocyte (rs = -0.61), hemoglobin (rs = -0.54), hematocrit (rs = -0.52) and high-sensitivity C-reactive protein (rs = 0.58), all p < 0.05. A greater amount of oxygen uptake during post-walking recovery is partially related to lower skeletal muscle mass, greater arterial stiffness, reduced number of erythrocytes and higher systemic inflammation in post-stroke individuals.

A Music-Based Digital Therapeutic: Proof-of-Concept Automation of a Progressive and Individualized Rhythm-Based Walking Training Program After Stroke

BACKGROUND

The rhythm of music can entrain neurons in motor cortex by way of direct connections between auditory and motor brain regions.

OBJECTIVE

We sought to automate an individualized and progressive music-based, walking rehabilitation program using real-time sensor data in combination with decision algorithms.

METHODS

A music-based digital therapeutic was developed to maintain high sound quality while modulating, in real-time, the tempo (ie, beats per minute, or bpm) of music based on a user's ability to entrain to the tempo and progress to faster walking cadences in-sync with the progression of the tempo. Eleven individuals with chronic hemiparesis completed one automated 30-minute training visit. Seven returned for 2 additional visits. Safety, feasibility, and rehabilitative potential (ie, changes in walking speed relative to clinically meaningful change scores) were evaluated.

RESULTS

A single, fully automated training visit resulted in increased usual (∆ 0.085 ± 0.027 m/s, P = .011) and fast (∆ 0.093 ± 0.032 m/s, P = .016) walking speeds. The 7 participants who completed additional training visits increased their usual walking speed by 0.12 ± 0.03 m/s after only 3 days of training. Changes in walking speed were highly related to changes in walking cadence (R² > 0.70). No trips or falls were noted during training, all users reported that the device helped them walk faster, and 70% indicated that they would use it most or all of the time at home.

CONCLUSIONS

In this proof-of-concept study, we show that a sensor-automated, progressive, and individualized rhythmic locomotor training program can be implemented safely and effectively to train walking speed after stroke. Music-based digital therapeutics have the potential to facilitate salient, community-based rehabilitation.

Forced and Voluntary Aerobic Cycling Interventions Improve Walking Capacity in Individuals With Chronic Stroke

OBJECTIVES

To determine the efficacy of high-intensity cycling to improve walking capacity in individuals with chronic stroke, identify variables that predict improvement in walking capacity, and quantify the relationship between the 6-minute walk test (6MWT) and cardiopulmonary exercise (CPX) test variables.

DESIGN

Secondary analysis of data from 2 randomized controlled trials.

SETTING

Research laboratory.

PARTICIPANTS

Individuals with chronic stroke (N=43).

INTERVENTIONS

Participants were randomized to 1 of the following time-matched interventions, occurring 3 times per week for 8 weeks: (1) forced aerobic exercise and upper extremity repetitive task practice (FE+RTP [n=16]), (2) voluntary aerobic exercise and upper extremity repetitive task practice (VE+RTP [n=14]), or (3) a non-aerobic control group (n=13).

MAIN OUTCOME MEASURE

Change in walking capacity as measured by the 6MWT from baseline to the end of treatment (EOT).

RESULTS

Significant increases were observed in distance traveled during the 6MWT at the EOT compared with baseline in the FE+RTP (P<.001) and VE+RTP (P<.001) groups, but not in the control group (P=.21). Among aerobic exercise participants, a multivariate regression analysis revealed that cycling cadence, power output, and baseline 6MWT distance were significant predictors of change in walking capacity.

CONCLUSIONS

An 8-week aerobic cycling intervention prescribed at 60% to 80% of heart rate reserve and moderate to high cadence and resistance led to significant improvements in walking capacity in our cohort of individuals with chronic stroke. Individuals with low baseline walking capacity levels may benefit most from aerobic cycling to improve over ground locomotion. Although the 6MWT did not elicit a cardiorespiratory response comparable to the maximal exertion CPX test, the 6MWT can be considered a valid and clinically relevant submaximal test of cardiorespiratory function in individuals with chronic stroke.