Aerobic exercise interventions for promoting cardiovascular health and mobility after stroke: a systematic review with Bayesian network meta-analysis.

OBJECTIVE: To determine the superiority of aerobic exercise (AE) interventions on key outcomes of stroke recovery, including cardiorespiratory fitness (V̇O2peak, primary outcome), systolic blood pressure (SBP) and mobility (6 min Walk Test (6MWT) distance and 10 m Usual Gait Speed) after stroke. DATA SOURCES: MEDLINE, EMBASE, Web of Science, CINAHL, CENTRAL, SPORTDiscus, PsycINFO and AMED Allied and Complementary Medicine were searched from inception to February 2023. ELIGIBILITY CRITERIA: Randomised controlled trials were included that compared the effects of any AE interventions (low-intensity, moderate-intensity, high-intensity continuous training (HICT), high-intensity interval training (HIIT)) to no exercise, usual care or other AE interventions in individuals poststroke. ANALYSES: Systematic review with Bayesian network meta-analysis (NMA) methodology was employed. Surface under the cumulative ranking curve (SUCRA) values were used to rank interventions. The Grading of Recommendations, Assessment, Development and Evaluation minimally contextualised framework for NMA was followed. RESULTS: There were 28 studies (n=1298) included in the NMA for V̇O2peak, 11 (n=648) for SBP, 28 (n=1494) for 6MWT and 18 (n=775) for the 10 m Usual Gait Speed. The greatest effect on V̇O2peak, 6MWT and 10 m Usual Gait Speed was observed after HIIT and HICT. No differences between interventions were found for SBP. SUCRA values identified HIIT as the superior AE intervention for all outcomes of interest. HIIT was the most effective intervention for improving V̇O2peak (2.9 mL/kg/min (95% credible interval 0.8 to 5.0) moderate certainty) compared with usual care. CONCLUSION: This NMA suggests that higher-intensity AE is superior to traditional low-intensity to moderate-intensity AE for improving outcomes after stroke.

Exercising the Sleepy-ing Brain: Exercise, Sleep, and Sleep Loss on Memory.

We examine the novel hypothesis that physical exercise and sleep have synergistic effects on memory. Exercise can trigger mechanisms that can create an optimal brain state during sleep to facilitate memory processing. The possibility that exercise could counteract the deleterious effects of sleep deprivation on memory by protecting neuroplasticity also is discussed.

Exploring differences between gender expressions in exercise self-efficacy and outcome expectations for exercise in individuals with stroke.

Gender expression may be associated with exercise self-efficacy and outcome expectations for exercise in the general population. Exercising for challenge and enjoyment are associated with the instrumental traits typically held by individuals with masculine gender expressions. Conversely, exercising for weight loss to receive validation from others are in line with the expressive traits most commonly held by individuals with feminine gender expressions. Moreover, possessing neither dominant nor expressive traits (undifferentiated gender expressions) have been linked to poorer psychological outcomes. Exercise is important after stroke, but gender differences in psychosocial factors for exercise in this population were unknown. The purpose of this study was to explore whether gender expression differences exist in exercise self-efficacy and outcome expectations for exercise post-stroke. Gender expression (masculine, feminine, androgynous, undifferentiated) was assessed using the Bem Sex-Role Inventory-12 (BSRI-12) in 67 individuals with stroke. Self-efficacy and outcomes expectations for exercise were assessed using the Self-Efficacy for Physical Activity Scale and Short Outcome Expectations for Exercise Scale, respectively. One-way analysis of covariance models were conducted, adjusting for biological sex, age, and time post-stroke. There were differences in exercise self-efficacy across the four gender expression groups (F(3,60) = 4.28, p<0.01), where individuals with masculine gender expressions had higher self-efficacy than those with undifferentiated gender expressions (adjusted mean: 3.56 [SE: 0.17] vs. 2.72 [SE:0.18], p<0.01). There were no differences in outcome expectations for exercise (F(3,57) = 1.08, p = 0.36) between gender expressions. In our pairwise comparisons, we found that individuals with masculine gender expressions had higher exercise self-efficacy than individuals possessing undifferentiated gender expressions. Strategies to enhance exercise self-efficacy after stroke are needed, particularly for individuals with undifferentiated gender expression. There were no associations between gender expression and outcome expectations for exercise after stroke. Clinicians may continue reinforcing the positive expectations towards exercise across all gender expressions.

Measuring Neuroplasticity in Response to Cardiovascular Exercise in People With Stroke: A Critical Perspective.

BACKGROUND: Rehabilitative treatments that promote neuroplasticity are believed to improve recovery after stroke. Animal studies have shown that cardiovascular exercise (CE) promotes neuroplasticity but the effects of this intervention on the human brain and its implications for the functional recovery of patients remain unclear. The use of biomarkers has enabled the assessment of cellular and molecular events that occur in the central nervous system after brain injury. Some of these biomarkers have proven to be particularly valuable for the diagnosis of severity, prognosis of recovery, as well as for measuring the neuroplastic response to different treatments after stroke. OBJECTIVES: To provide a critical analysis on the current evidence supporting the use of neurophysiological, neuroimaging, and blood biomarkers to assess the neuroplastic response to CE in individuals poststroke. RESULTS: Most biomarkers used are responsive to the effects of acute and chronic CE interventions, but the response appears to be variable and is not consistently associated with functional improvements. Small sample sizes, methodological variability, incomplete information regarding patient's characteristics, inadequate standardization of training parameters, and lack of reporting of associations with functional outcomes preclude the quantification of the neuroplastic effects of CE poststroke using biomarkers. CONCLUSION: Consensus on the optimal biomarkers to monitor the neuroplastic response to CE is currently lacking. By addressing critical methodological issues, future studies could advance our understanding of the use of biomarkers to measure the impact of CE on neuroplasticity and functional recovery in patients with stroke.

Does the Brain-Derived Neurotrophic Factor Val66Met Polymorphism Modulate the Effects of Physical Activity and Exercise on Cognition?

The Val66Met is a polymorphism of the brain-derived neurotrophic factor (BDNF) gene that encodes a substitution of a valine (Val) to methionine (Met) amino acid. Carrying this polymorphism reduces the activity-dependent secretion of the BDNF protein, which can potentially affect brain plasticity and cognition. We reviewed the biology of Val66Met and surveyed 26 studies (11,417 participants) that examined the role of this polymorphism in moderating the cognitive response to physical activity (PA) and exercise. Nine observational studies confirmed a moderating effect of Val66Met on the cognitive response to PA but differences between Val and Met carriers were inconsistent and only significant in some cognitive domains. Only five interventional studies found a moderating effect of Val66Met on the cognitive response to exercise, which was also inconsistent in its direction. Two studies showed a superior cognitive response in Val carriers and three studies showed a better response in Met carriers. These results do not support a general and consistent effect of Val66Met in moderating the cognitive response to PA or exercise. Both Val and Met carriers can improve specific aspects of cognition by increasing PA and engaging in exercise. Causes for discrepancies among studies, effect moderators, and future directions are discussed.

Exercise-Based Stroke Rehabilitation: Clinical Considerations Following the COVID-19 Pandemic.

Background. The COVID-19 pandemic attributable to the severe acute respiratory syndrome virus (SARS-CoV-2) has had a significant and continuing impact across all areas of healthcare including stroke. Individuals post-stroke are at high risk for infection, disease severity, and mortality after COVID-19 infection. Exercise stroke rehabilitation programs remain critical for individuals recovering from stroke to mitigate risk factors and morbidity associated with the potential long-term consequences of COVID-19. There is currently no exercise rehabilitation guidance for people post-stroke with a history of COVID-19 infection. Purpose. To (1) review the multi-system pathophysiology of COVID-19 related to stroke and exercise; (2) discuss the multi-system benefits of exercise for individuals post-stroke with suspected or confirmed COVID-19 infection; and (3) provide clinical considerations related to COVID-19 for exercise during stroke rehabilitation. This article is intended for healthcare professionals involved in the implementation of exercise rehabilitation for individuals post-stroke who have suspected or confirmed COVID-19 infection and non-infected individuals who want to receive safe exercise rehabilitation. Results. Our clinical considerations integrate pre-COVID-19 stroke (n = 2) and COVID-19 exercise guidelines for non-stroke populations (athletic [n = 6], pulmonary [n = 1], cardiac [n = 2]), COVID-19 pathophysiology literature, considerations of stroke rehabilitation practices, and exercise physiology principles. A clinical decision-making tool for COVID-19 screening and eligibility for stroke exercise rehabilitation is provided, along with key subjective and physiological measures to guide exercise prescription. Conclusion. We propose that this framework promotes safe exercise programming within stroke rehabilitation for COVID-19 and future infectious disease outbreaks.

The association between global cognitive function and walking capacity in individuals with broad ranges of cognitive and physical function: Are there sex differences?

Introduction: Cognitive function is known to be associated with physical function, where greater walking capacity has been shown to have moderate to strong correlations with global cognitive function and other various domains of cognition in older adults with and without chronic conditions. Biological sex may moderate the relationship between cognitive and physical function, but whether sex differences exist in this association has not been examined in an aging population. The purpose of this study was to examine the associations between global cognitive function (Montreal Cognitive Assessment; MoCA), walking capacity (6-Minute Walk Test distance; 6 MWT) and sex in an aging population with broad ranges of cognitive and physical function. Methods: Participants were assessed for global cognitive function (MoCA) and walking capacity (6 MWT). Multivariable regression analyses were performed to examine the interaction of sex in the association between MoCA and 6 MWT. First, we presented the unadjusted model (Model 1), then the model adjusted for age, history of stroke, and height (Model 2). To determine if there were sex-based differences in the association between global cognitive function and walking capacity, we included sex and an interaction term between sex*6 MWT distance in Models 3 and 4. Results: Twenty-three females and 36 males were included in the multivariable regression analyses, respectively. Our sample represented broad ranges of cognitive and physical function levels, where MoCA scores ranged from 13 to 30, and 6 MWT distances from 203 to 750 m. 6 MWT distance was associated with MoCA in models unadjusted (R 2 = 0.17; F(1,56) = 11.4; p < 0.01) and adjusted for age, stroke history, and height (R 2 = 0.20; F(4,53) = 3.2; p = 0.02). No interaction with sex was found, but a main effect of sex was observed (R 2 = 0.26; F(5,21) = 3.72; p = 0.03). When adjusting for age, height and history of stroke, males MoCA scores were 2.9 ± 1.3 less than the mean MoCA scores for females. Discussion: Our findings confirm the positive relationship between cognitive and physical function in older adults. Notably, we also observed superior performance in global cognition among females that was consistent across a broad spectrum of walking capacity.

Intensity matters: protocol for a randomized controlled trial exercise intervention for individuals with chronic stroke.

RATIONALE: Cardiovascular exercise is an effective method to improve cardiovascular health outcomes, but also promote neuroplasticity during stroke recovery. Moderate-intensity continuous cardiovascular training (MICT) is an integral part of stroke rehabilitation, yet it may remain a challenge to exercise at sufficiently high intensities to produce beneficial adaptations to neuroplasticity. High-intensity interval training (HIIT) could provide a viable alternative to achieve higher intensities of exercise by using shorter bouts of intense exercise interspersed with periods of recovery. METHODS AND DESIGN: This is a two-arm, parallel-group multi-site RCT conducted at the Jewish Rehabilitation Hospital (Laval, Québec, Canada) and McMaster University (Hamilton, Ontario, Canada). Eighty participants with chronic stroke will be recruited at both sites and will be randomly allocated into a HIIT or MICT individualized exercise program on a recumbent stepper, 3 days per week for 12 weeks. Outcomes will be assessed at baseline, at 12 weeks post-intervention, and at an 8-week follow-up. OUTCOMES: The primary outcome is corticospinal excitability, a neuroplasticity marker in brain motor networks, assessed with transcranial magnetic stimulation (TMS). We will also examine additional markers of neuroplasticity, measures of cardiovascular health, motor function, and psychosocial responses to training. DISCUSSION: This trial will contribute novel insights into the effectiveness of HIIT to promote neuroplasticity in individuals with chronic stroke. TRIAL REGISTRATION: ClinicalTrials.gov NCT03614585 . Registered on 3 August 2018.

Exercise Improves Video Game Performance: A Win-Win Situation.

PURPOSE: Video gamers exceeding screen-time limits are at greater risk of experiencing health issues associated with physical inactivity. Demonstrating that exercise has positive effects on video game performance could promote physical activity among video gamers. We investigated the short-term effects of a single session of cardiovascular exercise on the performance of the popular video game League of Legends (LoL) and explored psychosocial mechanisms. METHODS: Twenty young video gamers played a customized LoL task preceded by a short bout of high-intensity interval training or a period of rest. The two conditions were administered on two separate days in a randomized counterbalanced fashion. Video game performance was assessed as the total number of targets eliminated as well as accuracy, defined as the ability to eliminate targets using single attacks. Short-term changes in affect after exercise as well as exercise enjoyment were also assessed. RESULTS: Exercise improved (P = 0.027) the capacity to eliminate targets (mean ± SEM, 121.17 ± 3.78) compared with rest (111.38 ± 3.43). Exercise also enhanced accuracy (P = 0.019), with fewer targets eliminated with more than one attack after exercise (1.39 ± 0.39) compared with rest (2.44 ± 0.51). Exercise increased positive affect by 17% (P = 0.007), but neither affect nor exercise enjoyment was associated with total number of targets eliminated or accuracy. CONCLUSION: A short bout of intense cardiovascular exercise before playing LoL improves video game performance. More studies are needed to establish whether these effects are generalizable to other video games, whether repeated bouts have summative effects, and to identify underlying mechanisms.

Effects of an 8-week training cessation period on cognition and functional capacity in older adults.

BACKGROUND: Multiple types of exercise interventions have been described as effective methods for improving cognition and mobility in older adults. In addition to combined strength and aerobic training, gross motor activities have shown benefits. However, adherence to exercise is a challenge, which may bring about periods of training cessation. Importantly, short-term training cessation may lead to a loss of fitness adaptations. The effects of training cessation on cognition and functional capacity are not well known, especially within the context of dual-tasking in older adults. OBJECTIVES: We examined the effects of an 8-week training cessation period on cognition (executive functioning (EF) in single (ST) and dual-task (DT)) and functional capacity (10 m Walk and 6 Minute Walk Test) of healthy older adults, after one of three training interventions: combined lower body strength and aerobic, combined upper body strength and aerobic, or gross motor activities. MATERIALS AND METHODS: Forty older adults (70.5 ± 5.5 years, 67.5% F) participated in training sessions, 3×/week for 8 weeks prior to training cessation. Pre (T0), post (T1) and follow-up (post-cessation, T2) measures of EF (performance in inhibition and updating/working memory indices of the Random Number Generation task) in ST and DT (treadmill walking at 0.67 m·s-1, 1.11 m·s-1, and 1.56 m·s-1), and functional capacity were assessed. Changes in ST and DT as well as functional capacity tests were analyzed using two-way ANOVAs (time ∗ group) with repeated measures for the time factor (T0, T1 and T2). RESULTS: Improvements in inhibition indices were observed in ST for all time comparisons (T0-T1, T1-T2 and T0-T2). Inhibition in DT improved from T0-T2 and from T1-T2. Working memory declined from T0-T2 and from T1-T2. Functional capacity performance was maintained from T1-T2 (small improvement from T0-T1 and from T0-T2). DISCUSSION: Performances in inhibition were maintained or improved after cessation of training. We found no interaction between training groups, whatever the condition, indicating similar training cessation effects regardless of the intervention. CONCLUSIONS: Multiple types of exercise interventions may lead to positive benefit to inhibition and functional capacity in older adults, and it may also be possible to retain these benefits after a short cessation period.