Premotor and Posterior Parietal Cortex Activity is Increased for Slow, as well as Fast Walking Poststroke: An fNIRS Study.

Methods: Twenty individuals in the chronic stage of stroke walked: (1) at their normal pace, (2) slower than normal, and (3) as fast as possible. Functional near-infrared spectroscopy was used to assess bilateral prefrontal, premotor, sensorimotor, and posterior parietal cortices during walking. Results: No significant differences in laterality were observed between walking speeds. The ipsilesional prefrontal cortex was overall more active than the contralesional prefrontal cortex. Premotor and posterior parietal cortex activity were larger during slow and fast walking compared to normal-paced walking with no differences between slow and fast walking. Greater increases in brain activation in the ipsilesional prefrontal cortex during fast compared to normal-paced walking related to greater gait speed modulation. Conclusions: Brain activation is not linearly related to gait speed. Ipsilesional prefrontal cortex, bilateral premotor, and bilateral posterior parietal cortices are important areas for gait speed modulation and could be an area of interest for neurostimulation.

Brain activity during real-time walking and with walking interventions after stroke: a systematic review.

Investigations of real-time brain activations during walking have become increasingly important to aid in recovery of walking after a stroke. Individual brain activation patterns can be a valuable biomarker of neuroplasticity during the rehabilitation process and can result in improved personalized medicine for rehabilitation. The purpose of this systematic review is to explore the brain activation characteristics during walking post-stroke by determining: (1) if different components of gait (i.e., initiation/acceleration, steady-state, complex) result in different brain activations, (2) whether brain activations differ from healthy individuals. Six databases were searched resulting in 22 studies. Initiation/acceleration showed bilateral activation in frontal areas; steady-state and complex walking showed broad activations with the majority exploring and finding increases in frontal regions and some studies also showing increases in parietal activation. Asymmetrical activations were often related to performance asymmetry and were more common in studies with slower gait speed. Hyperactivations and asymmetrical activations commonly decreased with walking interventions and as walking performance improved. Hyperactivations often persisted in individuals who had experienced severe strokes. Only a third of the studies included comparisons to a healthy group: individuals post-stroke employed greater brain activation compared to young adults, while comparisons to older adults were less clear and limited. Current literature suggests some indicators of walking recovery however future studies investigating more brain regions and comparisons with healthy age-matched adults are needed to further understand the effect of stroke on walking-related brain activation.

Neuroplasticity of Cortical Planning for Initiating Stepping Poststroke: A Case Series.

BACKGROUND AND PURPOSE: Therapeutic exercise improves balance and walking ability in individuals after stroke. The extent to which motor planning improves with therapeutic exercise is unknown. This case series examined how outpatient physical therapy affects motor planning and motor performance for stepping. CASE DESCRIPTION: Individuals poststroke performed self-initiated stepping before (baseline), after (postintervention), and 1 month after (retention) intervention. Amplitude and duration of the movement-related cortical potential (MRCP) was measured using an electroencephalograph from the Cz electrode. Electromyography (EMG) of biceps femoris (BF) was collected. Additionally, clinical measures of motor impairment and function were evaluated at all 3 time points by a blinded assessor. INTERVENTION: Two types of outpatient physical therapy were performed for 6 weeks: CONVENTIONAL (n = 3) and FAST (n = 4, Fast muscle Activation and Stepping Training). OUTCOMES: All 7 participants reduced MRCP duration, irrespective of the type of physical therapy. The MRCP amplitude and BF EMG onset changes were more variable. Clinical outcomes improved or were maintained for all participants. The extent of motor impairment was associated with MRCP amplitude. DISCUSSION: Changes in MRCP duration suggest that outpatient physical therapy may promote neuroplasticity of motor planning of stepping movements after stroke; however, a larger sample is needed to determine whether this finding is valid.This case series suggests motor planning for initiating stepping may improve after 6 weeks of outpatient physical therapy for persons with stroke.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A307).

Passive, yet not inactive: robotic exoskeleton walking increases cortical activation dependent on task.

BACKGROUND: Experimental designs using surrogate gait-like movements, such as in functional magnetic resonance imaging (MRI), cannot fully capture the cortical activation associated with overground gait. Overground gait in a robotic exoskeleton may be an ideal tool to generate controlled sensorimotor stimulation of gait conditions like 'active' (i.e. user moves with the device) and 'passive' (i.e. user is moved by the device) gait. To truly understand these neural mechanisms, functional near-infrared spectroscopy (fNIRS) would yield greater ecological validity. Thus, the aim of this experiment was to use fNIRS to delineate brain activation differences between 'Active' and 'Passive' overground gait in a robotic exoskeleton. METHODS: Fourteen healthy adults performed 10 walking trials in a robotic exoskeleton for Passive and Active conditions, with fNIRS over bilateral frontal and parietal lobes, and electromyography (EMG) over bilateral thigh muscles. Digitization of optode locations and individual T1 MRI scans were used to demarcate the brain regions fNIRS recorded from. RESULTS: Increased oxyhemoglobin in the right frontal cortex was found for Passive compared with Active conditions. For deoxyhemoglobin, increased activation during Passive was found in the left frontal cortex and bilateral parietal cortices compared with Active; one channel in the left parietal cortex decreased during Active when compared with Passive. Normalized EMG mean amplitude was higher in the Active compared with Passive conditions for all four muscles (p ≤ 0.044), confirming participants produced the conditions asked of them. CONCLUSIONS: The parietal cortex is active during passive robotic exoskeleton gait, a novel finding as research to date has not recorded posterior to the primary somatosensory cortex. Increased activation of the parietal cortex may be related to the planning of limb coordination while maintaining postural control. Future neurorehabilitation research could use fNIRS to examine whether exoskeletal gait training can increase gait-related brain activation with individuals unable to walk independently.

The Impact of Covert Lacunar Infarcts and White Matter Hyperintensities on Cognitive and Motor Outcomes After Stroke.

BACKGROUND AND AIMS: In addition to overt stroke lesions, co-occurring covert lesions, including white matter hyperintensities (WMH) and covert lacunar infarcts (CLI), contribute to poststroke outcome. The purpose of this study was to examine the relationship between covert lesions, and motor and cognitive outcomes in individuals with chronic stroke. METHODS: Volumetric quantification of clinically overt strokes, covert lesions (periventricular and deep: pWMH, dWMH, pCLI, dCLI), ventricular and sulcal CSF (vCSF, sCSF), and normal appearing white (NAWM) and gray matter (NAGM) was performed using structural magnetic resonance imaging. We assessed motor impairment and function, and global cognition, memory, and other cognitive domains. When correlation analysis identified more than one MR parameter relating to stroke outcomes, we used regression modeling to identify which factor had the strongest impact. RESULTS: Neuropsychological and brain imaging data were collected from 30 participants at least 6 months following a clinically diagnosed stroke. Memory performance related to vCSF (r = -0.52, P = .004). The strongest predictor of nonmemory domains was pCLI (r2 = 0.28, P = .004). Motor impairment and function were most strongly predicted by the volume of stroke and NAWM (r2 = 0.36; P = .001), and dWMH (r2 = 0.39; P = .001) respectively. CONCLUSIONS: Covert lesion type and location have important consequences for post-stroke cognitive and motor outcome. Limiting the progression of covert lesions in aging populations may enhance the degree of recovery post-stroke.

Suppression of somatosensory stimuli during motor planning may explain levels of balance and mobility after stroke.

The ability to actively suppress, or gate, irrelevant sensory information is required for safe and efficient walking in sensory-rich environments. Both motor attention and motor planning alter somatosensory evoked potentials (SEPs) in healthy adults. This study's aim was to examine the effect of motor attention on processing of irrelevant somatosensory information during plantar flexion motor planning after stroke. Thirteen healthy older adults and 11 individuals with stroke participated. Irrelevant tibial nerve stimulation was delivered while SEPs were recorded over Cz, overlaying the leg portion of the sensorimotor cortex at the vertex of the head. Three conditions were tested in both legs: (1) Rest, (2) Attend To, and (3) Attend Away from the stimulated limb. In conditions 2 and 3, relevant vibration cued voluntary plantar flexion movements of the stimulated (Attend To) or non-stimulated (Attend Away) leg. SEP amplitudes were averaged during motor planning per condition. Individuals with stroke did not show attention-mediated gating of the N40 component associated with irrelevant somatosensory information during motor planning. It may be that dysfunction in pathways connecting to area 3b explains the lack of attention-mediated gating of the N40. Also, attention-mediated gating during motor planning explained significant and unique variance in a measure of community balance and mobility combined with response time. Thus, the ability to gate irrelevant somatosensory information appears important for stepping in both older adults and after stroke. Our data suggest that therapies that direct motor attention could positively impact walking after stroke.

Selectivity of conventional electrodes for recording motor evoked potentials: An investigation with high-density surface electromyography.

INTRODUCTION: The objective of this study was to determine whether motor evoked potentials (MEPs) elicited with transcranial magnetic stimulation and measured with conventional bipolar electromyography (EMG) are influenced by crosstalk from non-target muscles. METHODS: MEPs were recorded in healthy participants using conventional EMG electrodes placed over the extensor carpi radialis muscle (ECR) and high-density surface EMG (HDsEMG). Fifty MEPs at 120% resting and active motor threshold were recorded. To determine the contribution of ECR to the MEPs, the amplitude distribution across HDsEMG channels was correlated with EMG activity recorded during a wrist extension task. RESULTS: Whereas the conventional EMG identified MEPs from ECR in >90% of the stimulations, HDsEMG revealed that spatial amplitude distribution representative of ECR activation was observed less frequently at rest than while holding a contraction (P < 0.001). CONCLUSIONS: MEPs recorded with conventional EMG may contain crosstalk from non-target muscles, especially when the stimulation is applied at rest. Muscle Nerve 55: 828-834, 2017.

Interhemispheric Pathways Are Important for Motor Outcome in Individuals with Chronic and Severe Upper Limb Impairment Post Stroke.

Background: Severity of arm impairment alone does not explain motor outcomes in people with severe impairment post stroke. Objective: Define the contribution of brain biomarkers to upper limb motor outcomes in people with severe arm impairment post stroke. Methods: Paretic arm impairment (Fugl-Meyer upper limb, FM-UL) and function (Wolf Motor Function Test rate, WMFT-rate) were measured in 15 individuals with severe (FM-UL ≤ 30/66) and 14 with mild-moderate (FM-UL > 40/66) impairment. Transcranial magnetic stimulation and diffusion weight imaging indexed structure and function of the corticospinal tract and corpus callosum. Separate models of the relationship between possible biomarkers and motor outcomes at a single chronic (≥6 months) time point post stroke were performed. Results: Age (ΔR20.365, p = 0.017) and ipsilesional-transcallosal inhibition (ΔR20.182, p = 0.048) explained a 54.7% (p = 0.009) variance in paretic WMFT-rate. Prefrontal corpus callous fractional anisotropy (PF-CC FA) alone explained 49.3% (p = 0.007) variance in FM-UL outcome. The same models did not explain significant variance in mild-moderate stroke. In the severe group, k-means cluster analysis of PF-CC FA distinguished two subgroups, separated by a clinically meaningful and significant difference in motor impairment (p = 0.049) and function (p = 0.006) outcomes. Conclusion: Corpus callosum function and structure were identified as possible biomarkers of motor outcome in people with chronic and severe arm impairment.

Motor Planning for Loading During Gait in Subacute Stroke.

OBJECTIVES: To determine the characteristics of motor planning surrounding initial contact during gait through examination of thigh muscle timing, amplitude, and co-contraction of the paretic and nonparetic limbs in people poststroke, and to investigate whether muscle timing, amplitude, and clinical performance measures of balance and mobility differ based on the level of co-contraction. DESIGN: Observational study. SETTING: University-based research laboratory. PARTICIPANTS: Individuals (n=27) in the subacute phase after stroke and healthy controls (n=8) (N=35). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Timing (onset and offset) and normalized amplitude (percent electromyography maximum) of the biceps femoris (BF) and rectus femoris (RF) muscles were measured during terminal swing and early stance. A co-contraction index (CCI) was calculated for the BF and RF muscle activity. Individuals with CCI values equal to or below the mean of the healthy group were in the low CCI group, whereas those with values above the mean were in the high CCI group. Functional balance and mobility evaluation used the Community Balance and Mobility Scale (CB&M). RESULTS: For the paretic and nonparetic limbs, measures of timing, amplitude, and co-contraction were similar for both limbs. Compared with the healthy group, the high CCI group had lower CB&M scores, longer durations, and higher levels of RF and BF muscle activity, whereas the low CCI group had electromyographic measures statistically similar to healthy controls. CONCLUSIONS: The motor control of gait after subacute stroke is characterized by symmetry of timing and amplitude of muscle recruitment at the knee. High co-contraction levels surrounding the knee were associated with lower functional balance and mobility. These findings suggest a compensatory strategy of increased co-contraction in those with more impairment while maintaining symmetry of lower-limb biomechanics between limbs.

Motor Skill Acquisition Promotes Human Brain Myelin Plasticity.

Experience-dependent structural changes are widely evident in gray matter. Using diffusion weighted imaging (DWI), the neuroplastic effect of motor training on white matter in the brain has been demonstrated. However, in humans it is not known whether specific features of white matter relate to motor skill acquisition or if these structural changes are associated to functional network connectivity. Myelin can be objectively quantified in vivo and used to index specific experience-dependent change. In the current study, seventeen healthy young adults completed ten sessions of visuomotor skill training (10,000 total movements) using the right arm. Multicomponent relaxation imaging was performed before and after training. Significant increases in myelin water fraction, a quantitative measure of myelin, were observed in task dependent brain regions (left intraparietal sulcus [IPS] and left parieto-occipital sulcus). In addition, the rate of motor skill acquisition and overall change in myelin water fraction in the left IPS were negatively related, suggesting that a slower rate of learning resulted in greater neuroplastic change. This study provides the first evidence for experience-dependent changes in myelin that are associated with changes in skilled movements in healthy young adults.

Evaluating the Educational Experience of Physiotherapy Students Using the Fitness and Mobility Exercise (FAME) Programme to Learn about Neurological Conditions: An Exploratory Study.

Purpose: Group exercise has the potential to be a cost-effective way to improve functional outcomes for those living with neurological injury. Leading group exercise is a foundational competency for entry-to-practice for physiotherapy students. The overall objective of this study was to examine the student experience of using the Fitness and Mobility Exercise (FAME) programme to learn about neurological conditions in a group setting. Methods: Sixteen physiotherapy students filled out a single point in time survey at the end of their placement during which they had the opportunity to use FAME with their clients twice a week. The survey had Likert and open-ended questions and demographic information. Likert responses were calculated as means. Open-ended questions were analyzed using thematic analysis. Results: The Likert questions were answered with almost entirely positive results. The main themes from the open-ended questions were how to personalize the class, characteristics of individual clients shape the class experience and factors that make the class successful. Conclusions: Overall, the physiotherapy students found using FAME to be a positive experience. From the student perspective, using FAME during placement was an effective way to learn about neurological conditions as well as to develop skills to manage a group exercise class.

Objectif: les exercices de groupe ont le potentiel d'être un moyen rentable d'améliorer les résultats fonctionnels des personnes qui vivent avec une atteinte neurologique. La direction d'exercices de groupe est une compétence fondamentale d'accès à la pratique chez les étudiants en physiothérapie. L'objectif global de cette étude consistait à examiner l'expérience des étudiants à l'égard de l'utilisation du programme d'exercices pour la forme physique et la mobilité (FAME, d'après l'acronyme anglais Fitness and Mobility Exercise) et à en apprendre davantage sur les atteintes neurologiques dans un contexte de groupe. Méthodologie: au total, seize étudiants en physiothérapie ont rempli un seul sondage à la fin de leur stage, au cours duquel ils avaient pu utiliser le programme FAME deux fois par semaine avec leurs clients. Le sondage contenait des questions de type échelle de Likert, des questions ouvertes et des renseignements démographiques. Les chercheuses ont analysé les réponses de type échelle de Likert sous forme de moyennes et les questions ouvertes, sous forme d'analyse thématique. Résultats: les réponses aux questions de type échelle de Likert étaient presque toujours positives. Les principaux thèmes des questions ouvertes étaient comment personnaliser le cours, les caractéristiques des clients individuels façonnent l'expérience du cours et les facteurs qui font du cours une réussite. Conclusions: dans l'ensemble, les étudiants en physiothérapie ont trouvé que l'utilisation du programme FAME était une expérience positive. De l'avis des étudiants, l'utilisation du programme FAME pendant le stage était un moyen efficace d'en apprendre davantage au sujet des maladies neurologiques et d'acquérir des compétences pour gérer un cours d'exercice de groupe.

Standing middle cerebral artery velocity predicts cognitive function and gait speed in older adults with cognitive impairment, and is impacted by sex differences.

Upright posture challenges the cerebrovascular system, leading to changes in middle cerebral artery velocity (MCAv) dynamics which are less evident at supine rest. Chronic alterations in MCAv have been linked to hypoperfusion states and the effect that this may have on cognition remains unclear. This study aimed to determine if MCAv and oscillatory metrics of MCAv (ex. pulsatility index, PI) during upright posture are i) associated with cognitive function and gait speed (GS) to a greater extent than during supine rest, and ii) are different between sexes. Beat-by-beat MCAv (transcranial Doppler ultrasound) and mean arterial pressure (MAP, plethysmography) were averaged for 30-seconds during supine-rest through a transition to standing for 53 participants (73±6yrs, 17 females). While controlling for age, multiple linear regressions predicting MoCA scores and GS from age, supine MCAv metrics, and standing MCAv metrics, were completed. Simple linear regressions predicting Montreal Cognitive Assessment (MoCA) score and GS from MCAv metrics were performed separately for females and males. Significance was set to p<0.05. Lower standing diastolic MCAv was a significant (p = 0.017) predictor of lower MoCA scores in participants with mild cognitive impairment, and this relationship only remained significant for males. Lower standing PI was associated with slower GS (p = 0.027, r=-0.306) in both sexes. Our results indicate a relationship between blunted MCAv and altered oscillatory flow profiles during standing, with lower MoCA scores and GS. These relationships were not observed in the supine position, indicating a unique relationship between standing measures of MCAv with cognitive and physical functions.

Relationships amongst osteoarthritis biomarkers, dynamic knee joint load, and exercise: results from a randomized controlled pilot study.

BACKGROUND: Little is known about the relationships of circulating levels of biomarkers of cartilage degradation with biomechanical outcomes relevant to knee osteoarthritis (OA) or biomarker changes following non-pharmacological interventions. The objectives of this exploratory, pilot study were to: 1) examine relationships between biomarkers of articular cartilage degradation and synthesis with measures of knee joint load during walking, and 2) examine changes in these biomarkers following 10 weeks of strengthening exercises. METHODS: Seventeen (8 male, 9 female; 66.1 +/- 11.3 years of age) individuals with radiographically-confirmed medial tibiofemoral OA participated. All participants underwent a baseline testing session where serum and urine samples were collected, followed by a three-dimensional motion analysis. Motion analysis was used to calculate the external knee adduction moment (KAM) peak value and impulse. Following baseline testing, participants were randomized to either 10 weeks of: 1) physiotherapist-supervised lower limb muscle strengthening exercises, or 2) no exercises (control). Identical follow-up testing was conducted 11 weeks after baseline. Biomarkers included: urinary C-telopeptide of type II collagen (uCTX-II) and type II collagen cleavage neoepitope (uC2C), serum cartilage oligomeric matrix protein (sCOMP), serum hyaluronic acid (sHA) and serum C-propeptide of type II procollagen (sCPII). Linear regression analysis was used to examine relationships between measures of the KAM and biomarker concentrations as baseline, as well as between-group differences following the intervention. RESULTS: KAM impulse predicted significant variation in uCTX-II levels at baseline (p = 0.04), though not when controlling for disease severity and walking speed (p = 0.33). KAM impulse explained significant variation in the ratio uCTX-II;sCPII even when controlling for additional variables (p = 0.04). Following the intervention, changes in sCOMP were significantly greater in the exercise group compared to controls (p = 0.04). On average those in the control group experienced a slight increase in sCOMP and uCTX-II, while those in the exercise group experienced a reduction. No other significant findings were observed. CONCLUSIONS: This research provides initial evidence of a potential relationship between uCTX-II and knee joint load measures in patients with medial tibiofemoral knee OA. However, this relationship became non-significant after controlling for disease severity and walking speed, suggesting further research is necessary. It also appears that sCOMP is amenable to change following a strengthening intervention, suggesting a potential beneficial role of exercise on cartilage structure. TRIAL REGISTRATION: Clinicaltrials.gov NCT01241812.

Rehabilitation Interventions for Physical Capacity and Quality of Life in Adults With Post-COVID-19 Condition: A Systematic Review and Meta-Analysis.

Importance: Current rehabilitation guidelines for patients with post-COVID-19 condition (PCC) are primarily based on expert opinions and observational data, and there is an urgent need for evidence-based rehabilitation interventions to support patients with PCC. Objective: To synthesize the findings of existing studies that report on physical capacity (including functional exercise capacity, muscle function, dyspnea, and respiratory function) and quality of life outcomes following rehabilitation interventions in patients with PCC. Data Sources: A systematic electronic search was performed from January 2020 until February 2023, in MEDLINE, Scopus, CINAHL, and the Clinical Trials Registry. Key terms that were used to identify potentially relevant studies included long-covid, post-covid, sequelae, exercise therapy, rehabilitation, physical activity, physical therapy, and randomized controlled trial. Study Selection: This study included randomized clinical trials that compared respiratory training and exercise-based rehabilitation interventions with either placebo, usual care, waiting list, or control in patients with PCC. Data Extraction and Synthesis: This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. A pairwise bayesian random-effects meta-analysis was performed using vague prior distributions. Risk of bias was assessed using the Cochrane risk of bias tool version 2, and the certainty of evidence was evaluated using the GRADE system by 2 independent researchers. Main Outcomes and Measures: The primary outcome was functional exercise capacity, measured at the closest postintervention time point by the 6-minute walking test. Secondary outcomes were fatigue, lower limb muscle function, dyspnea, respiratory function, and quality of life. All outcomes were defined a priori. Continuous outcomes were reported as standardized mean differences (SMDs) with 95% credible intervals (CrIs) and binary outcomes were summarized as odds ratios with 95% CrIs. The between-trial heterogeneity was quantified using the between-study variance, τ2, and 95% CrIs. Results: Of 1834 identified records, 1193 were screened, and 14 trials (1244 patients; 45% female participants; median [IQR] age, 50 [47 to 56] years) were included in the analyses. Rehabilitation interventions were associated with improvements in functional exercise capacity (SMD, -0.56; 95% CrI, -0.87 to -0.22) with moderate certainty in 7 trials (389 participants). These improvements had a 99% posterior probability of superiority when compared with current standard care. The value of τ2 (0.04; 95% CrI, 0.00 to 0.60) indicated low statistical heterogeneity. However, there was significant uncertainty and imprecision regarding the probability of experiencing exercise-induced adverse events (odds ratio, 1.68; 95% CrI, 0.32 to 9.94). Conclusions and Relevance: The findings of this systematic review and meta-analysis suggest that rehabilitation interventions are associated with improvements in functional exercise capacity, dyspnea, and quality of life, with a high probability of improvement compared with the current standard care; the certainty of evidence was moderate for functional exercise capacity and quality of life and low for other outcomes. Given the uncertainty surrounding the safety outcomes, additional trials with enhanced monitoring of adverse events are necessary.

Higher intensity walking improves global cognition during inpatient rehabilitation: a secondary analysis of a randomized control trial.

Cognitive deficits are common poststroke. Cognitive rehabilitation is typically used to improve cognitive deficits. It is unknown whether higher doses of exercise to promote motor recovery influence cognitive outcomes. Our recent trial, Determining Optimal Post-Stroke Exercise (DOSE), shows more than double the steps and aerobic minutes can be achieved during inpatient rehabilitation versus usual care, and translates to improved long-term walking outcomes. Thus, the secondary analysis aim was to determine the effect of the DOSE protocol on cognitive outcomes over 1-year poststroke. The DOSE protocol progressively increased step number and aerobic minutes during inpatient stroke rehabilitation over 20 sessions. The Montreal Cognitive Assessment (MoCA), Digit Symbol Substitution Test (DSST), and Trail Making Test B were completed at baseline, post-intervention, and 6- and 12-months poststroke, administered using standardized guidelines. Using the DOSE data, we used mixed-effect spline regression to model participants' trajectories of cognitive recovery, controlling for relevant covariates. Participants (Usual Care n = 25, DOSE n = 50) were 56.7(11.7) years old, and 27(10) days post stroke. For the MoCA, there were statistically significant Group × Trajectory(p = 0.019), and Group × ΔTrajectory (p = 0.018) interactions with a substantial clinically meaningful difference, from +5.44 points/month improvement of the DOSE group compared to +1.59 points/month improvement with Usual Care during the 4-week intervention. The DSST and Trails B improved over time but were not different between groups. Taking advantage of this early difference may lend support to continued efforts to increase intensity, during and after discharge from inpatient rehabilitation, to improve cognition. Clinical trial registration: www.clinicaltrials.gov, NCT01915368.

Implementation of increased physical therapy intensity for improving walking after stroke: Walk 'n watch protocol for a multisite stepped-wedge cluster-randomized controlled trial.

RATIONALE: Clinical practice guidelines support structured, progressive protocols for improving walking after stroke. Yet, practice is slow to change, evidenced by the little amount of walking activity in stroke rehabilitation units. Our recent study (n = 75) found that a structured, progressive protocol integrated with typical daily physical therapy improved walking and quality-of-life measures over usual care. Research therapists progressed the intensity of exercise by using heart rate and step counters worn by the participants with stroke during therapy. To have the greatest impact, our next step is to undertake an implementation trial to change practice across stroke units where we enable the entire unit to use the protocol as part of standard of care. AIMS: What is the effect of introducing structured, progressive exercise (termed the Walk 'n Watch protocol) to the standard of care on the primary outcome of walking in adult participants with stroke over the hospital inpatient rehabilitation period? Secondary outcomes will be evaluated and include quality of life. METHODS AND SAMPLE SIZE ESTIMATES: This national, multisite clinical trial will randomize 12 sites using a stepped-wedge design where each site will be randomized to deliver Usual Care initially for 4, 8, 12, or 16 months (three sites for each duration). Then, each site will switch to the Walk 'n Watch phase for the remaining duration of a total 20-month enrolment period. Each participant will be exposed to either Usual Care or Walk 'n Watch. The trial will enroll a total of 195 participants with stroke to achieve a power of 80% with a Type I error rate of 5%, allowing for 20% dropout. Participants will be medically stable adults post-stroke and able to take five steps with a maximum physical assistance from one therapist. The Walk 'n Watch protocol focuses on completing a minimum of 30 min of weight-bearing, walking-related activities (at the physical therapists' discretion) that progressively increase in intensity informed by activity trackers measuring heart rate and step number. STUDY OUTCOME(S): The primary outcome will be the change in walking endurance, measured by the 6-Minute Walk Test, from baseline (T1) to 4 weeks (T2). This change will be compared across Usual Care and Walk 'n Watch phases using a linear mixed-effects model. Additional physical, cognitive, and quality of life outcomes will be measured at T1, T2, and 12 months post-stroke (T3) by a blinded assessor. DISCUSSION: The implementation of stepped-wedge cluster-randomized trial enables the protocol to be tested under real-world conditions, involving all clinicians on the unit. It will result in all sites and all clinicians on the unit to gain expertise in protocol delivery. Hence, a deliberate outcome of the trial is facilitating changes in best practice to improve outcomes for participants with stroke in the trial and for the many participants with stroke admitted after the trial ends.

Length of course-based undergraduate research experiences (CURE) impacts student learning and attitudinal outcomes: A study of the Malate dehydrogenase CUREs Community (MCC).

Course-based undergraduate research experiences (CUREs) are laboratory courses that integrate broadly relevant problems, discovery, use of the scientific process, collaboration, and iteration to provide more students with research experiences than is possible in individually mentored faculty laboratories. Members of the national Malate dehydrogenase CUREs Community (MCC) investigated the differences in student impacts between traditional laboratory courses (control), a short module CURE within traditional laboratory courses (mCURE), and CUREs lasting the entire course (cCURE). The sample included approximately 1,500 students taught by 22 faculty at 19 institutions. We investigated course structures for elements of a CURE and student outcomes including student knowledge, student learning, student attitudes, interest in future research, overall experience, future GPA, and retention in STEM. We also disaggregated the data to investigate whether underrepresented minority (URM) outcomes were different from White and Asian students. We found that the less time students spent in the CURE the less the course was reported to contain experiences indicative of a CURE. The cCURE imparted the largest impacts for experimental design, career interests, and plans to conduct future research, while the remaining outcomes were similar between the three conditions. The mCURE student outcomes were similar to control courses for most outcomes measured in this study. However, for experimental design, the mCURE was not significantly different than either the control or cCURE. Comparing URM and White/Asian student outcomes indicated no difference for condition, except for interest in future research. Notably, the URM students in the mCURE condition had significantly higher interest in conducting research in the future than White/Asian students.

Quantifying Physical Resilience in Ageing Using Measurement Instruments: A Scoping Review.

Purpose: The capacity to recover motor function with pathology or age-related decline is termed physical resilience. It is unknown what outcome domains are captured with existing measurement instruments. Thus, this scoping review aimed to identify measurement instruments for physical resilience, identify research gaps, and make recommendations for future research. Methods: Articles were included from the search when their subject matter included the term resilience in relation to the physical health of older adults. Data on physical resilience measurement instruments were extracted using the outcome domains: body function or structure, activity and participation, and societal impact. Results: The majority of the 33 included articles involved older adults with fractures, cardiac conditions, and cancer. Many measurement instruments quantified body function or structure, and some instruments captured activity and participation, and societal impact of physical resilience. Measurement instruments were pooled into 4 categories: psychological, physiological, motor function, and psychosocial scales. No studies combined all areas of measurement. Conclusions: A potential gap of a measurement instrument capturing social aspects of physical resilience was identified. Comprehensive measurement could identify which outcome domains could be targeted to foster resilience. This knowledge might be useful across many health disciplines and contribute to therapeutic decision-making and rehabilitation strategies.

Objectif : la résilience physique désigne la capacité de recouvrer sa fonction motrice malgré le déclin lié à une pathologie ou à l'âge. On ne sait pas quels domaines de résultats cliniques les instruments de mesure actuels saisissent. Ainsi, la présente étude de portée visait à déterminer les instruments pour mesurer la résilience physique, repérer les lacunes de la recherche et faire des recommandations en vue des futures recherches. Méthodologie : les articles de la recherche étaient conservés lorsque leur sujet incluait le terme resilience à l'égard de la santé physique des personnes âgées. Les chercheurs ont extrait les données sur les instruments de mesure de la résilience physique au moyen des domaines de résultats suivants : fonction ou structure corporelle, l'activité et la participation et les répercussions sociétales. Résultats : la majorité des 33 articles inclus portaient sur des personnes âgées ayant des fractures, des affections cardiaques et un cancer. De nombreux instruments de mesure quantifiaient la fonction ou la structure corporelle et certains saisissaient l'activité, la participation et les répercussions sociétales de la résilience physique. Les chercheurs ont regroupé les instruments de mesure en quatre catégories : échelles psychologique, physiologique, de la fonction motrice et psychosociale. Aucune étude ne combinait tous les domaines de mesure. Conclusions : les chercheurs ont repéré une lacune potentielle d'un instrument qui saisit les aspects sociaux de la résilience physique. Une mesure exhaustive pourrait déterminer les domaines de résultat à cibler pour favoriser la résilience. Ces connaissances pourraient être utiles dans de nombreuses disciplines et contribuer aux décisions thérapeutiques et aux stratégies de réadaptation.

Frontal, Sensorimotor, and Posterior Parietal Regions Are Involved in Dual-Task Walking After Stroke.

Background: Walking within the community requires the ability to walk while simultaneously completing other tasks. After a stroke, completing an additional task while walking is significantly impaired, and it is unclear how the functional activity of the brain may impact this. Methods: Twenty individual in the chronic stage post-stroke participated in this study. Functional near-infrared spectroscopy (fNIRS) was used to measure prefrontal, pre-motor, sensorimotor, and posterior parietal cortices during walking and walking while completing secondary verbal tasks of varying difficulty. Changes in brain activity during these tasks were measured and relationships were accessed between brain activation changes and cognitive or motor abilities. Results: Significantly larger activations were found for prefrontal, pre-motor, and posterior parietal cortices during dual-task walking. Increasing dual-task walking challenge did not result in an increase in brain activation in these regions. Higher general cognition related to lower increases in activation during the easier dual-task. With the harder dual-task, a trend was also found for higher activation and less motor impairment. Conclusions: This is the first study to show that executive function, motor preparation/planning, and sensorimotor integration areas are all important for dual-task walking post-stroke. A lack of further brain activation increase with increasing challenge suggests a point at which a trade-off between brain activation and performance occurs. Further research is needed to determine if training would result in further increases in brain activity or improved performance.

Step Number and Aerobic Minute Exercise Prescription and Progression in Stroke: A Roadmap.

BACKGROUND: While higher therapeutic intensity improves motor recovery after stroke, translating findings from successful studies is challenging without clear exercise intensity targets. We show in the DOSE trial1 more than double the steps and aerobic minutes within a session can be achieved compared with usual care and translates to improved long-term walking outcomes. OBJECTIVE: We modeled data from this successful higher intensity multi-site RCT to develop targets for prescribing and progressing exercise for varying levels of walking impairment after stroke. METHODS: In twenty-five individuals in inpatient rehabilitation, twenty sessions were monitored for a total of 500 one-hour physical therapy sessions. For the 500 sessions, step number and aerobic minute progression were modeled using linear mixed effects regression. Using formulas from the linear mixed effects regression, targets were calculated. RESULTS: The model for step number included session number and baseline walking speed, and for aerobic minutes, session number and age. For steps, there was an increase of 73 steps per session. With baseline walking speed, for every 0.1 m/s increase, a corresponding increase of 302 steps was predicted. For aerobic minutes, there was an increase of .56 minutes of aerobic activity (ie, 34 seconds) per session. For every year increase in age, a decrease of .39 minutes (ie, 23 seconds) was predicted. CONCLUSIONS: Using data associated with better walking outcomes, we provide step number and aerobic minute targets that future studies can cross-validate. As walking speed and age are collected at admission, these models allow for uptake of routine measurement of therapeutic intensity.Registration: www.clinicaltrials.gov; NCT01915368.