Effect of low-intensity ergometer aerobic training on glucose tolerance in severely impaired nondiabetic stroke patients

Elucidating the role of physical exercises in alleviating stroke-associated homeostatic dysregulation: a systematic review and meta-analysis

Background

This study aimed to investigate the role of physical exercises as a non-pharmacological intervention for ameliorating post-stroke dysregulated homeostatic parameters.

Methods

Embase, PubMed, PEDro, ISI Web of Science and CENTRAL were searched until April 2024. Parallel randomised controlled trials (RCTs) analysing the effect of post-stroke physical exercises (PSPE) on homeostatic parameters such as blood glucose, oxygen consumption (VO2), high-density lipoprotein (HDL), low-density lipoprotein (LDL), systolic (SBP) and diastolic blood pressure (DBP) in individuals with stroke were selected.

Results

Sixteen RCTs (n=698) were included. PSPE reduced fasting glucose levels (MD=-0.22; 95% CI -0.22 to -0.02; p=0.00) and increased the VO2 (MD=2.51; 95% CI 1.65 to 3.37; p=0.00) and blood HDL levels (MD=0.07; 95% CI 0.00 to 0.13; p=0.00). However, we did not observe beneficial effects on LDL, SBP and DBP parameters. Further analyses demonstrated that both low and moderate exercises are more suitable for improving blood glucose and VO2 in this population.

Discussion

PSPE have the potential to improve dysregulated post-stroke parameters by reducing blood glucose levels and increasing VO2 and HDL levels. However, the small size and limited number of included studies limited the precision of our results. Further research is needed to comprehensively analyse the effects of PSPE, particularly on LDL levels and blood pressure.

PROSPERO registration number

CRD42023395715.

Effects of Assisted Walking Exercise in Chronic Dependent Ambulatory Stroke Survivors: A Mini-Review

Background

Assisted walking exercise programs are widely recommended in rehabilitation guidelines for stroke survivors. However, most evidence supporting these programs primarily focuses on ambulatory stroke survivors or those dependent ambulatory in acute and subacute stages. There is a notable gap in the application of walking exercise programs for chronic dependent ambulatory stroke survivors despite potential benefits in reducing sedentary behavior and improving rehabilitation outcomes. Thus, this literature review aims to summarize the existing evidence on the feasibility and efficacy of assisted walking exercise programs for chronic stroke survivors who are dependent ambulators.

Methods

Six major databases were searched for clinical trials related to assisted walking exercise and chronic dependent ambulatory stroke.

Results

Seven studies (evidence with low- to moderate-quality) involving 91 chronic dependent ambulatory stroke subjects are included in this review.

Conclusions

These studies indicated that assisted walking exercise is feasible to perform by chronic dependent ambulatory stroke survivors and can induce continued motor recovery and functional improvement. However, the mixed and limited evidence from existing research underscores the need for future high-quality randomized controlled trials with standardized designs and outcome measures to establish evidence-based walking programs for this population.

The implementation of sex-and gender-based considerations in exercise-based randomized controlled trials in individuals with stroke: A cross-sectional study

Emerging evidence suggests that sex-and gender-based factors may influence responses to exercise post-stroke. The Sex and Gender Equity in Research (SAGER) guidelines (2016) published international standards for terminology and considerations for research design and trial reporting. The extent to which sex- and gender-based considerations have been implemented in stroke exercise trials is currently unknown. The objective of this cross-sectional study was to compare the proportion of studies that have implemented sex/gender considerations before and after the publication of the SAGER guidelines. We conducted a comprehensive search of the literature to identify exercise-based trials in individuals with stroke. Study titles, abstracts, introductions (hypothesis statements), methods, results and discussions were assessed for adherence to the SAGER guidelines. The proportion of studies adhering to SAGER guidelines published prior to and including December 31, 2016 and from 2017-March 2023 were compared. Of the 245 studies identified, 150 were published before December 31, 2016, of which 0 (0%) titles/abstracts, 0 (0%) introductions, 21 (14.0%) methods, 8 (5.3%) results, and 7 (4.7%) discussion sections adhered to the SAGER guidelines, and 35 (23.3%) reported proper sex and gender terminology. Of the 95 studies published between 2017-2023, 0 (0%) title/abstracts, 1 (1.0%) introduction, 16 (16.8%) methods, 5 (5.3%) results, and 10 (10.5%) discussion sections adhered to the guidelines, and 37 (38.9%) of studies included proper terminology. The implementation of sex- and gender-based considerations in stroke exercise trials is low, but positively the reporting of proper terminology has increased since the publication of standardized reporting guidelines. This study serves as a call to action for stroke rehabilitation researchers to incorporate sex- and gender-based considerations in all stages of research studies, to improve the rigour and generalizability of findings, and promote health equity.

The effect of the multimodal intervention on blood pressure in patients with first ischemic stroke: A randomized controlled trial

Background

Multimodal intervention is currently promoted to control blood pressure in patients with first ischemic stroke. However, a dearth of studies has examined the influence of the intervention among patients with ischemic stroke, particularly in Thailand.

Objective

This study aimed to determine the effect of the multimodal intervention on blood pressure in patients with first ischemic stroke.

Methods

A randomized controlled trial was conducted. Sixty participants were randomly selected from two tertiary hospitals in Thailand. Eligible participants were randomly assigned into an experimental group (n = 30) and a control group (n = 30). The experimental group was provided with the multimodal intervention, while the control group was given the usual care. Data were collected from May 2021 to October 2021 at baseline (pre-test), 4^th week, 8^th week, and 12^th week using the demographic data form and sphygmomanometer. The data were analyzed using the Chi-square test, t-test, and repeated measure analysis of variance (ANOVA).

Results

The participants' blood pressures after receiving the multimodal intervention were lower than those before receiving the multimodal intervention. Both systolic and diastolic blood pressure were statistically significantly decreased over time, starting from baseline to the 8^th week and 12^th week (p <0.001). In addition, the participants' mean scores of systolic blood pressure (F (1, 58) = 4.059, p = 0.049) and diastolic blood pressure (F (1, 58) = 4.515, p = 0.038) were lower than the control group.

Conclusion

The multimodal intervention is effective in controlling blood pressure. Therefore, nurses should educate patients with ischemic stroke to manage systolic and diastolic blood pressure, facilitate the patient's participation in the exercise program, and monitor the patients via telephone to continue blood pressure control.

Trial Registry

Thai Clinical Trials Registry (TCTR) identifier number 20210318001.

Randomization to Treadmill Training Improves Physical and Metabolic Health in Association With Declines in Oxidative Stress in Stroke

OBJECTIVE

To investigate the effect of aerobic exercise vs control (stretching/balance) on inflammatory and oxidative stress biomarkers in stroke survivors and whether these changes are associated with improvements in physical and metabolic health.

DESIGN

Randomized controlled trial.

SETTING

The general communities of Baltimore, Maryland, and Atlanta, Georgia.

PARTICIPANTS

Two hundred forty-six older (>50 years), chronic (>6 months) survivors of stroke (N=246) with hemiparetic gait were recruited, with 51 completing pre-intervention testing and 39 completing postintervention testing. Participants were required to have completed all conventional physical therapy and be capable of walking 3 minutes on a treadmill (N=246).

INTERVENTION

Participants completed 6 months of 2 times/wk stretching or balance (ST; n=19) or 3 times/wk aerobic treadmill rehabilitation (TM; n=20;).

MAIN OUTCOME MEASURE(S)

Peak oxygen uptake rate (V̇o2peak), 6-minute walking distance (6MWD), fasting plasma glucose, insulin, oxidative stress, and inflammatory biomarkers were assessed pre- and postintervention. Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) was calculated.

RESULTS

Physical function and metabolic health parameters tended to improve after TM but not ST (ST vs TM: V̇o2peak: -9% vs 24%, P<.01; 6MWD: 1% vs 15%, P=.05; insulin: -1% vs -31%, P=.05; HOMA-IR: -3% vs -29%, P=.06). Plasma concentrations of nitrotyrosine, protein carbonyls, and oxidized low-density lipoprotein (oxLDL) tended to decrease from pre-intervention concentrations in response to TM compared to ST (ST vs TM: nitrotyrosine: 2% vs -28%, P=.01; protein carbonyls: -4% vs -34%, P=.08; oxLDL: -3% vs -32%, P<.01). Changes in circulating concentrations of C-reactive protein, protein carbonyls, and oxLDL were negatively associated with changes in V̇o2peak and 6MWD (r's=-0.40 to -0.76) and positively associated with fasting plasma insulin and HOMA-IR (r's=0.52-0.81, Ps<.01).

CONCLUSIONS

Six months of TM tends to be associated with increased functional capacity and reduced oxidative stress in chronic stroke survivors. Our findings identify potentially modifiable systemic markers of inflammation and oxidative stress important to stroke rehabilitation and provide potential targets for novel therapeutics in future studies.

The Role of Physical Therapy in Multiple Risk Factor Management Poststroke: A Scoping Review

BACKGROUND AND PURPOSE

Individuals after stroke often have multiple chronic conditions, such as hypertension, diabetes, dyslipidemia, obesity, and tobacco use. These comorbidities not only are commonly found in individuals with stroke, but also negatively affect functional outcomes and increase risk for hospital readmission and overall mortality. It is important for physical therapists to address the whole person during treatment after stroke, including comorbidities, not just the problems resulting from the stroke itself. However, it is unclear how common it is for physical therapists to address multiple diagnoses at once using a wellness model. Therefore, the purpose of this scoping review was to examine current evidence regarding the role of physical therapy in addressing modifiable risk factors for individuals after stroke, to identify gaps in research associated with physical therapy management of related comorbid diagnoses during treatment for stroke.

METHODS

A scoping review methodology was utilized searching PubMed and CINAHL databases to identify interventional research studies specifically addressing multiple modifiable risk factors utilizing physical therapy for individuals after stroke.

RESULTS

The initial search yielded 5358 articles and 12 articles met full inclusion criteria. Only 2 studies included participants with significant mobility impairments, and none included individuals with communication impairments. Only 4 of the 12 studies provided education in their design. Eight studies did not include any patient-reported outcome measures. Only 3 studies included long-term follow-up assessments.

DISCUSSION

Secondary stroke risk factors can be positively addressed using physical therapy interventions; however, more research is needed regarding individuals with moderate to severe mobility or communication deficits. Opportunities for physical therapy research to address stroke risk factors in this complex population include expanding follow-up periods, improving educational interventions, and including caregivers in study design.

CONCLUSIONS

This review highlights the need for better integration of clinical considerations into stroke rehabilitation research as a whole, along with the need for additional research regarding the role physical therapy can play in addressing multimorbidity in individuals with stroke.

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.

Effect of aerobic training on vascular and metabolic risk factors for recurrent stroke: a meta-analysis

AIM

This meta-analysis aimed to determine the effect of aerobic training, compared to non-aerobic interventions, on vascular and metabolic risk factors for recurrent stroke.

METHOD

This study was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines (PRISMA). Searches were performed in PubMed, Embase, Cochrane library and Cinahl up to May 8^th 2019. Randomized clinical trials evaluating the effect of solely aerobic training on vascular and metabolic risk factors for recurrent stroke were included in a meta-analysis if relevant outcomes were reported in at least two articles.

RESULTS

Our search resulted in a total of 7381 hits. Eleven outcomes out of nine articles were included in the meta-analysis. A significant positive effect of aerobic training was found on systolic blood pressure (-3.59 mmHg, 95% CI -6.14 to -1.05) and fasting glucose (-0.12 mmol/l, 95% CI -0.23 to -0.02). The effect on systolic blood pressure further improved when only high-quality studies were included (-4.95 mmHg, 95% CI -8.24 to -1.66).

CONCLUSION

Aerobic training results in a significant positive effect on systolic blood pressure and fasting glucose after stroke when compared to non-aerobic usual care or non-aerobic exercise.Implications for rehabilitationAerobic training has a positive effect on two of the most important vascular risk factors for recurrent stroke (i.e., systolic blood pressure and fasting glucose).The effect of solely aerobic training seems to be comparable to the effect of combined strength exercise and aerobic training for systolic blood pressure and fasting glucose.Since aerobic training has a significant effect on risk factors for recurrent stroke, implementation of aerobic training in daily life is important to reduce long term stroke risk.Previous research has showed that other metabolic risk factors can be altered by other interventions (e.g., strength exercise or lifestyle coaching), therefore, post-stroke prevention programs should be tailored in order to target specific risk-factors for individual patients.

Feasibility and trend of pulmonary function in a pilot trial of aerobic walking exercise in non-ambulatory stroke survivors

Background: Lung function is compromised in stroke survivors, which may cause fatigue and exercise intolerance. Furthermore, past studies of aerobic exercise have involved only stroke survivors who could walk independently. Stroke survivors who were unable to walk were not included in the previous research-investigating changes in lung function from walking exercise interventions. In this pilot study, the feasibility and the effect of aerobic walking exercise on lung function was examined in non-ambulatory stroke survivors using a treadmill, bodyweight support system, and a gait training device.Methods: This study was a single group trial. Eight non-ambulatory stroke survivors (five males, mean age 63.3 ± 13.7 years, seven with ischemic stroke) completed a low intensity walking exercise program (30 min/session; three sessions/week for 8 weeks) and lung function test. Before and after the intervention, vital capacity (VC) and forced vital capacity (FVC) using a spirometer were measured according to the guideline from American Thoracic Society/European Respiratory Society.Results: The rates of compliance and attrition were 100% and 10%; respectively, and no adverse events were reported. There were significant differences between pre- and post-intervention assessments in FVC (p = .09), percentage of predicted VC (p = .08), and percentage of predicted FVC (p = .08).Conclusions: In non-ambulatory stroke survivors, aerobic walking exercise is feasible and safe. Also, the results are promising and suggest that aerobic walking exercise may improve lung function; more data are needed.

Physical Fitness Training in Patients with Subacute Stroke (PHYS-STROKE): multicentre, randomised controlled, endpoint blinded trial

OBJECTIVE

To determine the safety and efficacy of aerobic exercise on activities of daily living in the subacute phase after stroke.

DESIGN

Multicentre, randomised controlled, endpoint blinded trial.

SETTING

Seven inpatient rehabilitation sites in Germany (2013-17).

PARTICIPANTS

200 adults with subacute stroke (days 5-45 after stroke) with a median National Institutes of Health stroke scale (NIHSS, range 0-42 points, higher values indicating more severe strokes) score of 8 (interquartile range 5-12) were randomly assigned (1:1) to aerobic physical fitness training (n=105) or relaxation sessions (n=95, control group) in addition to standard care.

INTERVENTION

Participants received either aerobic, bodyweight supported, treadmill based physical fitness training or relaxation sessions, each for 25 minutes, five times weekly for four weeks, in addition to standard rehabilitation therapy. Investigators and endpoint assessors were masked to treatment assignment.

MAIN OUTCOME MEASURES

The primary outcomes were change in maximal walking speed (m/s) in the 10 m walking test and change in Barthel index scores (range 0-100 points, higher scores indicating less disability) three months after stroke compared with baseline. Safety outcomes were recurrent cardiovascular events, including stroke, hospital readmissions, and death within three months after stroke. Efficacy was tested with analysis of covariance for each primary outcome in the full analysis set. Multiple imputation was used to account for missing values.

RESULTS

Compared with relaxation, aerobic physical fitness training did not result in a significantly higher mean change in maximal walking speed (adjusted treatment effect 0.1 m/s (95% confidence interval 0.0 to 0.2 m/s), P=0.23) or mean change in Barthel index score (0 (-5 to 5), P=0.99) at three months after stroke. A higher rate of serious adverse events was observed in the aerobic group compared with relaxation group (incidence rate ratio 1.81, 95% confidence interval 0.97 to 3.36).

CONCLUSIONS

Among moderately to severely affected adults with subacute stroke, aerobic bodyweight supported, treadmill based physical fitness training was not superior to relaxation sessions for maximal walking speed and Barthel index score but did suggest higher rates of adverse events. These results do not appear to support the use of aerobic bodyweight supported fitness training in people with subacute stroke to improve activities of daily living or maximal walking speed and should be considered in future guidelines.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01953549.

Ergometer cycling improves the ambulatory function and cardiovascular fitness of stroke patients-a randomized controlled trial

[Purpose] The aim of this study was to assess the effects of ergometer cycling on the ambulatory function and cardiovascular fitness of patients with stroke in the sub-acute phase. [Participants and Methods] Twenty (20) patients with stroke in the sub-acute phase were randomly allocated to either an ergometer cycling group (n=10) or a control group (n=10). The experimental (ergometer cycling) group performed cycling exercises in addition to conventional physiotherapy for 60 minutes per session, three times per week for 8 weeks. The control group only received conventional physiotherapy for the same duration as the experimental group. Assessments of participants' functional ambulatory category, ambulatory velocity, 6-minute walk test, heart rate and blood pressure were conducted at baseline and at the end of the 8-week intervention. [Results] The means of the ambulatory velocity and distance walked in 6 minutes were significantly higher in the ergometer cycling group than those of the control group at week 8. However, the increase in the FAC score was not significant. The means of heart rate, systolic and diastolic blood pressures significantly decreased in the ergometer cycling group compared to the control group at the end of the 8-week of intervention. [Conclusion] This study demonstrated that ergometer cycling improved the ambulatory function and cardiovascular fitness of patients with stroke in the sub-acute phase.

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.

Aerobic exercise interventions reduce blood pressure in patients after stroke or transient ischaemic attack: a systematic review and meta-analysis

OBJECTIVE

Secondary vascular risk reduction is critical to preventing recurrent stroke. We aimed to evaluate the effect of exercise interventions on vascular risk factors and recurrent ischaemic events after stroke or transient ischaemic attack (TIA).

DESIGN

Intervention systematic review and meta-analysis.

DATA SOURCES

OVID MEDLINE, PubMed, The Cochrane Library, Web of Science, The National Institute for Health and Care Excellence, TRIP Database, CINAHL, PsycINFO, SCOPUS, UK Clinical Trials Gateway and the China National Knowledge Infrastructure were searched from 1966 to October 2017.

ELIGIBILITY CRITERIA

Randomised controlled trials evaluating aerobic or resistance exercise interventions on vascular risk factors and recurrent ischaemic events among patients with stroke or TIA, compared with control.

RESULTS

Twenty studies (n=1031) were included. Exercise interventions resulted in significant reductions in systolic blood pressure (SBP) -4.30 mm Hg (95% CI -6.77 to -1.83) and diastolic blood pressure -2.58 mm Hg (95% CI -4.7 to -0.46) compared with control. Reduction in SBP was most pronounced among studies initiating exercise within 6 months of stroke or TIA (-8.46 mm Hg, 95% CI -12.18 to -4.75 vs -2.33 mm Hg, 95% CI -3.94 to -0.72), and in those incorporating an educational component (-7.81 mm Hg, 95% CI -14.34 to -1.28 vs -2.78 mm Hg, 95% CI -4.33 to -1.23). Exercise was also associated with reductions in total cholesterol (-0.27 mmol/L, 95% CI -0.54 to 0.00), but not fasting glucose or body mass index. One trial reported reductions in secondary vascular events with exercise, but was insufficiently powered.

SUMMARY

Exercise interventions can result in clinically meaningful blood pressure reductions, particularly if initiated early and alongside education.

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.

Intensifying Functional Task Practice to Meet Aerobic Training Guidelines in Stroke Survivors

Objective: To determine whether stroke survivors could maintain workloads during functional task practice that can reach moderate levels of cardiometabolic stress (i.e., ≥40% oxygen uptake reserve ([Formula: see text]O2R) for ≥20 min) without the use of ergometer-based exercise. Design: Cross-sectional study using convenience sampling. Setting: Research laboratory in a tertiary rehabilitation hospital. Participants: Chronic hemiparetic stroke survivors (>6-months) who could provide consent and walk with or without assistance. Intervention: A single bout of intermittent functional training (IFT). The IFT protocol lasted 30 min and involved performing impairment specific multi-joint task-oriented movements structured into circuits lasting ~3 min and allowing 30-45 s recovery between circuits. The aim was to achieve an average heart rate (HR) 30-50 beats above resting without using traditional ergometer-based aerobic exercise. Outcome measures: Attainment of indicators for moderate intensity aerobic exercise. Oxygen uptake ([Formula: see text]O2), carbon dioxide production ([Formula: see text]CO2), and HR were recorded throughout the 30 min IFT protocol. Values were reported as percentage of [Formula: see text]O2R, HR reserve (HRR) and HRR calculated from predicted maximum HR (HRRpred), which were determined from a prior maximal graded exercise test. Results: Ten (3-female) chronic (38 ± 33 months) stroke survivors (70% ischemic) with significant residual impairments (NIHSS: 3 ± 2) and a high prevalence of comorbid conditions (80% ≥ 1) participated. IFT significantly increased all measures of exercise intensity compared to resting levels: [Formula: see text]O2 (Δ 820 ± 290 ml min-1, p < 0.001), HR (Δ 42 ± 14 bpm, p < 0.001), and energy expenditure (EE; Δ 4.0 ± 1.4 kcal min-1, p < 0.001). Also, mean values for percentage of [Formula: see text]O2R (62 ± 19), HRR (55 ± 14), and HRRpred (52 ± 18) were significantly higher than the minimum threshold (40%) indicating achievement of moderate intensity aerobic exercise (p = 0.004, 0.016, and 0.043, respectively). Conclusion: Sufficient workloads to achieve moderate levels of cardiometabolic stress can be maintained in chronic stroke survivors using impairment-focused functional movements that are not dependent on ergometers or other specialized equipment.

Physical fitness training for stroke patients

BACKGROUND

Levels of physical fitness are low after stroke. It is unknown whether improving physical fitness after stroke reduces disability.

OBJECTIVES

To determine whether fitness training after stroke reduces death, dependence, and disability and to assess the effects of training with regard to adverse events, risk factors, physical fitness, mobility, physical function, quality of life, mood, and cognitive function. Interventions to improve cognitive function have attracted increased attention after being identified as the highest rated research priority for life after stroke. Therefore we have added this class of outcomes to this updated review.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched February 2015), the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 1: searched February 2015), MEDLINE (1966 to February 2015), EMBASE (1980 to February 2015), CINAHL (1982 to February 2015), SPORTDiscus (1949 to February 2015), and five additional databases (February 2015). We also searched ongoing trials registers, handsearched relevant journals 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 trials, assessed quality and risk of bias, and extracted data. We analysed data using random-effects meta-analyses. Diverse outcome measures limited the intended analyses.

MAIN RESULTS

We included 58 trials, involving 2797 participants, which comprised cardiorespiratory interventions (28 trials, 1408 participants), resistance interventions (13 trials, 432 participants), and mixed training interventions (17 trials, 957 participants). Thirteen deaths occurred before the end of the intervention and a further nine before the end of follow-up. No dependence data were reported. Diverse outcome measures restricted pooling of data. Global indices of disability show moderate improvement after cardiorespiratory training (standardised mean difference (SMD) 0.52, 95% confidence interval (CI) 0.19 to 0.84; P value = 0.002) and by a small amount after mixed training (SMD 0.26, 95% CI 0.04 to 0.49; P value = 0.02); benefits at follow-up (i.e. after training had stopped) were unclear. There were too few data to assess the effects of resistance training.Cardiorespiratory training involving walking improved maximum walking speed (mean difference (MD) 6.71 metres per minute, 95% CI 2.73 to 10.69), preferred gait speed (MD 4.28 metres per minute, 95% CI 1.71 to 6.84), and walking capacity (MD 30.29 metres in six minutes, 95% CI 16.19 to 44.39) at the end of the intervention. Mixed training, involving walking, increased preferred walking speed (MD 4.54 metres per minute, 95% CI 0.95 to 8.14), and walking capacity (MD 41.60 metres per six minutes, 95% CI 25.25 to 57.95). Balance scores improved slightly after mixed training (SMD 0.27, 95% CI 0.07 to 0.47). Some mobility benefits also persisted at the end of follow-up. The variability, quality of the included trials, and lack of data prevents conclusions about other outcomes and limits generalisability of the observed results.

AUTHORS' CONCLUSIONS

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 the speed and tolerance of walking; some improvement in balance could also occur. There is insufficient evidence to support the use of resistance training. The effects of training on death and dependence after stroke are still unclear but these outcomes are rarely observed in physical fitness training trials. 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 and identify long-term benefits.