Physiological Effects of Exercise on Stroke Survivors

Comparative efficacy of different exercise methods to improve cardiopulmonary function in stroke patients: a network meta-analysis of randomized controlled trials

Background

Although some studies have shown that exercise has a good effect on improving the cardiopulmonary function of stroke patients, it still needs to be determined which exercise method does this more effectively. We, therefore, aimed to evaluate the effectiveness of different exercise methods in improving cardiovascular function in stroke patients through a network meta-analysis (NMA), providing a basis to select the best treatment plan for stroke patients.

Methods

We systematically searched CNKI, WanFang, VIP, CBM, PubMed, Embase, Web of Science, and The Cochrane Library databases from establishment to 30 April 2023. Randomized controlled trials (RCTS) on exercise improving cardiopulmonary function in stroke patients were included, and we screened the included articles and extracted the relevant data. RevMan (version 5.4) and Stata (version 17.0) were used for data analysis.

Results

We included 35 RCTs and a total of 2,008 subjects. Intervention measures included high-intensity interval training (HIIT), aerobic training (AT), resistance training (RT), combined aerobic and resistance exercise (CE), and conventional therapy (CT). In the network meta-analysis, the surface under the cumulative ranking area (SUCRA) ranking result indicated that HIIT improved peak oxygen uptake (VO2peak) and 6 mins walking distance (6MWD) optimally, with rankings of HIIT (100.0%) > CE (70.5%) > AT (50.2%) > RT (27.7%) > CT (1.6%), and HIIT (90.9%) > RT (60.6%) > AT (48.9%) > RT (48.1%) > CT (1.5%), respectively. The SUCRA ranking result showed that CE improved systolic blood pressure (SBP) and diastolic blood pressure (DBP) optimally, with rankings of CE (82.1%) > HIIT (49.8%) > AT (35.3%) > CT (32.8%), and CE (86.7%) > AT (45.0%) > HIIT (39.5%) > CT (28.8%), respectively.

Conclusion

We showed that exercise can effectively improve the cardiopulmonary function of stroke patients. HIIT was the most effective in improving VO2peak and 6MWD in stroke patients. CE was the most effective in improving SBP and DBP in stroke patients. However, due to the limitations of existing clinical studies and evidence, larger sample size, multi-center, and high-quality RCTs are needed to verify the above conclusions in the future.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier [CRD42023436773].

Biomarkers associated with functional improvement after stroke rehabilitation: a systematic review and meta-analysis of randomized controlled trials

Objective

This study aims to identify blood and cerebrospinal fluid biomarkers that are correlated to the functional improvement of stroke patients after rehabilitation therapy, and provide ideas for the treatment and evaluation of stroke patients.

Methods

The PubMed, Web of Science, and Embase databases were searched for articles published in the English language, from inception to December 8, 2022.

Results

A total of 9,810 independent records generated 50 high-quality randomized controlled trials on 119 biomarkers. Among these records, 37 articles were included for the meta-analysis (with a total of 2,567 stroke patients), and 101 peripheral blood and cerebrospinal fluid biomarkers were included for the qualitative analysis. The quantitative analysis results revealed a moderate quality evidence that stroke rehabilitation significantly increased the level of brain-derived neurotrophic factor (BDNF) in serum. Furthermore, the low-quality evidence revealed that stroke rehabilitation significantly increased the concentration of serum noradrenaline (NE), peripheral blood superoxide dismutase (SOD), peripheral blood albumin (ALB), peripheral blood hemoglobin (HB), and peripheral blood catalase (CAT), but significantly decreased the concentration of serum endothelin (ET) and glutamate. In addition, the changes in concentration of these biomarkers were associated with significant improvements in post-stroke function. The serum BNDF suggests that this can be used as a biomarker for non-invasive brain stimulation (NIBS) therapy, and to predict the improvement of stroke patients.

Conclusion

The concentration of serum BNDF, NE, ET and glutamate, and peripheral blood SOD, ALB, HB and CAT may suggest the function improvement of stroke patients.

Influences of Breathing Exercises and Breathing Exercise Combined with Aerobic Exercise on Changes in Basic Spirometry Parameters in Patients with Bronchial Asthma

Scientific evidence shows that breathing or aerobic programs can improve the quality of life of asthma patients. The aim of this work was to find out the influences of breathing exercises and breathing exercises combined with aerobic exercise on changes in spirometry parameters in patients with bronchial asthma. Participants: The group consisted of 33 women with bronchial asthma—mild to moderate persistent levels of FEV1 reduction (80–50%)—with a mean age of 34.73 ± 1.53 years. They were randomly assigned to experimental group 1 (EX1), experimental group 2 (EX2) or the control group (CG). Materials and methods: Changes in spirometry parameters were evaluated over a 16-week period in the three groups: CG (placebo), EX1 (breathing exercises) and EX 2 (combination of breathing exercises with an aerobic program). To evaluate the pre-training and post-training diagnostics, we used MIR Spirobank II. The influences of the experimental and control factors were assessed using the following dependent variables: forced vital capacity (FVC), forced expiratory volume in one second (FEV1), Tiffeneau–Pinelli index (FEV1/FVC ratio), peak expiratory flow (PEF) and forced mid-expiratory flow (FEF25–75%). We used the Wilcoxon t-test and the Kruskal–Wallis test to evaluate the differences in the measured parameters. To examine the effect of our protocols, we used effect size (ES). Results: In CG we observed improvements in: FVC—(5%; p < 0.05; ES = 0.437). FEV1—(7.33%; p < 0.01; ES = 0.585). FEV1/FVC ratio (5.27%; p < 0.01; ES = 0.570). PEF (11.22%; p < 0.01; ES = 0.448). FEF25–75% (7.02%; p < 0.01; ES = 0.628). In EX1 we observed improvements in: FVC (5.23%; p < 0.01; ES = 0.631), FEV1 (20.67%; p < 0.01; ES = 0.627), FEV1/FVC ratio (16.06%; p < 0.01; ES = 0.628), PEF (13.35%; p < 0.01; ES = 0.627) and FEF25–75% (13.75%; p < 0.01; ES = 0.607). In EX2 we observed improvements in: FVC (9.12%; p < 0.01; ES = 0.627), FEV1 (27.37%; p < 0.01; ES = 0.626), FEV1/FVC ratio (15.32%; p < 0.01; ES = 0.610), PEF (30.66%; p < 0.01; ES = 0.626) and FEF25–75% (58.99%; p < 0.01; ES = 0.626). Significant differences compared to the control group were observed in EX1 for FEV1 (p < 0.05) and FEV1/FVC ratio (p < 0.01); and in EX2 for FEV1 (p < 0.05), FEV1/FVC ratio (p < 0.01), PEF (p < 0.05) and FEF (p < 0.05). A significant difference between EX1 and EX2 was observed in PEF (p < 0.05). Conclusions: It appears to be that combination of breathing exercises with aerobic activities is a more beneficial option for patients with bronchial asthma.

Combined Aerobic and Resistance Training for Cardiorespiratory Fitness, Muscle Strength, and Walking Capacity after Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

Cardiorespiratory fitness, measured as peak oxygen consumption, is a potent predictor of stroke risk. Muscle weakness is the most prominent impairment after stroke and is directly associated with reduced walking capacity. There is a lack of recommendations for optimal combined aerobic training and resistance training for those patients. The purpose of this study was to systematically review and quantify the effects of exercise training on cardiorespiratory fitness, muscle strength, and walking capacity after stroke.

METHODS

Five electronic databases were searched (until May 2019) for studies that met the following criteria: (1) adult humans with a history of stroke who ambulate independently; (2) structured exercise intervention based on combined aerobic training and resistance training; and (3) measured cardiorespiratory fitness, muscle strength, and/or walking capacity.

RESULTS

Eighteen studies (602 participants, average age 62 years) met the inclusion criteria. Exercise training significantly improved all 3 outcomes. In subgroup analyses for cardiorespiratory fitness, longer training duration was significantly associated with larger effect size. Likewise, for muscle strength, moderate weekly frequency and lower training volume were significantly associated with larger effect size. Furthermore, in walking capacity, moderate weekly frequency and longer training duration were significantly associated with larger effect size.

CONCLUSIONS

These results suggest that an exercise program consisting of moderate-intensity, 3 days per week, for 20 weeks should be considered for greater effect on cardiorespiratory fitness, muscle strength, and walking capacity in stroke patients.

Effects of breathing exercises on resting metabolic rate and maximal oxygen uptake

[Purpose] The aim of the present study is to examine effects of diaphragm breathing exercise and feedback breathing exercise on maximal oxygen uptake and resting metabolic rate. [Participants and Methods] Thirty-eight healthy participants were randomly assigned to two groups; the diaphragm breathing exercise group and the feedback breathing exercise group. The diaphragm breathing exercise group was asked to perform diaphragm respiration, and the feedback breathing exercise group was asked to breathe with feedback breathing device. Maximal oxygen uptake and resting metabolic rate were measured before and after two breathing exercises. [Results] Significant difference was found in maximal oxygen uptake before and after two breathing exercises. There was also significant difference in resting metabolic rate before and after diaphragm breathing exercise. However, significant difference was not found in resting metabolic rate before and after feedback breathing exercise. There were not significant between-group differences in both maximal oxygen uptake and resting metabolic rate. [Conclusion] Diaphragm breathing exercise and feedback breathing exercise could influence maximal oxygen uptake. Diaphragm breathing exercise could influence resting metabolic rate, but feedback breathing exercise could not.

Effect of diaphragm breathing exercise applied on the basis of overload principle

[Purpose] The purpose of this study was to examine effects of diaphragm breathing exercise applied on the basis overload principle on respiratory function. [Subjects and Methods] The subjects of this study were 35 normal adults. They were randomly assigned to two group; the maneuver-diaphragm exercise group and self-diaphragm exercise group. The respiratory function was evaluated using the CardioTouch 3000S (BIONET, Korea) as a pulmometry device. [Results] The maneuver-diaphragm exercise was more effective on functional vital capacity and forced expiratory volume at one second when compared to the self-diaphragm exercise. [Conclusion] According to the results of this study, although the self-diaphragm exercise did not show effects as much as the maneuver one, but the self-diaphragm exercise had a similar effects as the maneuver-diaphragm exercise. The self-diaphragmatic respiration applied on the basis of overload principle may be used as an effective respiratory exercise as a part of home respiration program.

Effects of diaphragm breathing exercise and feedback breathing exercise on pulmonary function in healthy adults

[Purpose] The present study investigated effects of diaphragm breathing exercise and feedback breathing exercise on respiratory function. [Subjects and Methods] Thirty-one subjects were randomly assigned to two groups; the feedback breathing exercise group and the maneuver-diaphragm exercise group. The feedback breathing exercise group was asked to breathe with feedback breathing device, and the maneuver-diaphragm exercise group was asked to perform diaphragm respiration. Respiratory function was evaluated when a subject sat on a chair comfortably. [Results] There was a significant difference in the functional vital capacity and slow vital capacity before and after all breathing exercises. There was a significant between-group difference in functional vital capacity. However, no between-group difference was found in slow vital capacity. [Conclusion] Diaphragm breathing exercise and feedback breathing exercise can affect respiratory function.

Effects of breathing exercises on lung capacity and muscle activities of elderly smokers

[Purpose] Elderly smokers have a reduced chest diameter due to weakening of the respiratory muscles, and this results in decreased ventilation, leading to a vicious circle. Therefore, the present study investigated the effects of an intervention program to enhance the pulmonary function and muscle activity of elderly smokers. [Subjects and Methods] Participants were randomly assigned to one of two experimental groups or a control (CG) group. The experimental groups performed exercises three times per week for six weeks, whereas the CG performed no exercises. One of the experimental groups performed a Feedback Breathing Exercise (FBE) for 15 minutes, and the other repeated three sets of Balloon-Blowing Exercises (BBE) with sufficient rest of more than one minute between sets. [Results] In the experimental groups, FVC, FEV1/FVC, PEF and muscle activity of the rectus abdominis significantly improved after four weeks, but no significant differences were observed in FEV1 or VC after six weeks. [Conclusion] The results show that FBE and BBE improved the pulmonary functions of elderly smokers, demonstrating the potential benefits of the development of various training methods using balloons, and group programs, including recreational factors, for increasing respiratory muscles strength.

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.

The effects of respiratory muscle strengthening exercise using a sling on the amount of respiration

[Purpose] The purpose of this study was to present aerobic exercise that can be performed together with respiratory muscle strength training and examine whether the vital capacity of individuals can be enhanced when respiratory muscle strength training is conducted together with aerobic exercise. [Subjects and Methods] The subjects were 10 male students and 8 female students. The sling exercise method was used to conduct three types of training to strengthen the muscles around the shoulder joints. A maximal respiratory quotient measurement device was used to measure the vital capacity of the subjects five times. [Results] There was a significant difference in each respiratory training time point compared with before the performance of respiratory training. [Conclusion] This study presented respiratory muscle strength training using a sling as a training method for respiratory training.

Ottawa Panel Evidence-Based Clinical Practice Guidelines for Post-Stroke Rehabilitation

BACKGROUND AND PURPOSE

The purpose of this project was to create guidelines for 13 types of physical rehabilitation interventions used in the management of adult patients (>18 years of age) presenting with hemiplegia or hemiparesis following a single clinically identifiable ischemic or hemorrhagic cerebrovascular accident (CVA).

METHOD

Using Cochrane Collaboration methods, the Ottawa Methods Group identified and synthesized evidence from comparative controlled trials. The group then formed an expert panel, which developed a set of criteria for grading the strength of the evidence and the recommendation. Patient-important outcomes were determined through consensus, provided that these outcomes were assessed with a validated and reliable scale.

RESULTS

The Ottawa Panel developed 147 positive recommendations of clinical benefit concerning the use of different types of physical rehabilitation interventions involved in post-stroke rehabilitation.

DISCUSSION AND CONCLUSION

The Ottawa Panel recommends the use of therapeutic exercise, task-oriented training, biofeedback, gait training, balance training, constraint-induced movement therapy, treatment of shoulder subluxation, electrical stimulation, transcutaneous electrical nerve stimulation, therapeutic ultrasound, acupuncture, and intensity and organization of rehabilitation in the management of post stroke.

Effects of respiratory muscle and endurance training using an individualized training device on the pulmonary function and exercise capacity in stroke patients

BACKGROUND

Because respiratory muscle function plays a strong role in exercise capacity and cardiopulmonary response to exercise, systematic training and measurement of respiratory muscle function should be considered in stroke patients. The purpose of this study was to determine whether an individualized respiratory muscle training device combined with conventional physical therapy exercise can improve the pulmonary function and exercise capacity of stroke patients.

MATERIAL AND METHODS

Twenty stroke patients were randomly assigned to an exercise group (n=10) or a control group (n=10). Over 4 weeks, each group participated in exercise training interventions 3 times per week. In each session, the control group received basic exercise treatments for 30 min, followed by an automated full-body workout for 20 min. The exercise group performed the same exercise regimen as the control group, as well as an additional respiratory muscle training regimen using a respiratory exercise device for 20 min.

RESULTS

Pulmonary function of forced vital capacity (FVC), forced expiratory volume at 1 s (FEV1), FEV1/FVC, and peak expiratory flow (PEF) and exercise capacity of a 6-min walking test and Shortness of Breath Modified Borg Dyspnea Scale (SBMBDS) scores were assessed before and after the training. A significant intergroup difference was observed in the FVC, FEV1, PEF, 6MWT, and SBMBDS scores (p<0.05).

CONCLUSIONS

These findings suggest that exercise of the respiratory muscles using an individualized respiratory device had a positive effect on pulmonary function and exercise capacity and may be used for breathing rehabilitation in stroke patients.

The effects on the pulmonary function of normal adults proprioceptive neuromuscular facilitation respiration pattern exercise

[Purpose] The purpose of this study was to determine whether proprioceptive neuromuscular facilitation (PNF) respiration exercise increases the pulmonary function of normal adults. [Subjects and Methods] Twenty-eight normal adults in their 20s were randomly assigned to an experimental group (n=14) or control group (n=14). Over the course of four weeks, the experimental group participated in PNF respiration pattern exercises for 30 minutes three times per week. Subjects were assessed pre-test and post-test by measurement of pulmonary function (tidal volume, inspiratory reserve volume, expiratory reserve volume, inspiratory capacity, and vital capacity). [Results] Our findings show that the experimental group had significant improvements in expiratory reserve volume and vital capacity. In the comparison of the two groups, the experimental group had higher pulmonary function than the control group. [Conclusion] In this study, the experimental group showed greater improvement in pulmonary function than the control group, which indicates that the PNF respiration exercise is effective at increasing the pulmonary function of normal adults.

Application of principles of exercise training in sub-acute and chronic stroke survivors: a systematic review

BACKGROUND

There is increasing evidence for the beneficial effects of exercise training in stroke survivors. In order to reach the desired training effects, exercise training principles must be considered as this ensures the prescription of adequate exercises at an adequate dose. Moreover, exercise training interventions must be designed in a way that maximizes patients' adherence to the prescribed exercise regimen. The objectives of this systematic review were (1) to investigate whether training principles for physical exercise interventions are reported in RCTs for sub-acute and chronic stroke survivors, (2) to evaluate whether the RCTs reported the prescription of the FITT components of the exercise interventions as well as (3) patients' adherence to this prescription, and (4) to assess the risk of bias of the included studies.

METHODS

We performed a systematic review of RCTs with exercise training as the primary intervention and muscular strength and/or endurance as primary outcomes. The Cochrane library's risk of bias (ROB) tool was used to judge the methodological quality of RCTs.

RESULTS

Thirty-seven RCTs were included in this systematic review. Eighteen studies (48.7%) focused on aerobic, 8 (21.6%) on resistance and 11 (29.7%) on combined interventions of aerobic and resistive strength exercise. Twenty-nine studies (78.4%) included only chronic stroke survivors, 5 studies (13.5%) only sub-acute stroke survivors whilst 3 studies (8.1%) included both. In terms of principle of exercise training, 89% reported specificity, 75.7% progression, 48.7% overload, 37.8% initial values, 32.4% reversibility and 13.5% diminishing returns. One RCT described all principles of physical exercise training and 19 (51.4%) all FITT components. Patients' adherence to exercise prescription was accounted for in 3 studies (8.1%). Failure to report blinding in patients and participants and failure to report allocation concealment were the most prevalent methodological shortcomings.

CONCLUSIONS

Incomplete and inconsistent reporting of (1) training components, (2) underlying exercise training principles and (3) patient adherence together with (4) a broad variation in the methodological quality of the included RCTs limit both the utility and reproducibility of physical exercise programs in stroke patients.

What is the evidence for physical therapy poststroke? A systematic review and meta-analysis

BACKGROUND

Physical therapy (PT) is one of the key disciplines in interdisciplinary stroke rehabilitation. The aim of this systematic review was to provide an update of the evidence for stroke rehabilitation interventions in the domain of PT.

METHODS AND FINDINGS

Randomized controlled trials (RCTs) regarding PT in stroke rehabilitation were retrieved through a systematic search. Outcomes were classified according to the ICF. RCTs with a low risk of bias were quantitatively analyzed. Differences between phases poststroke were explored in subgroup analyses. A best evidence synthesis was performed for neurological treatment approaches. The search yielded 467 RCTs (N = 25373; median PEDro score 6 [IQR 5-7]), identifying 53 interventions. No adverse events were reported. Strong evidence was found for significant positive effects of 13 interventions related to gait, 11 interventions related to arm-hand activities, 1 intervention for ADL, and 3 interventions for physical fitness. Summary Effect Sizes (SESs) ranged from 0.17 (95%CI 0.03-0.70; I(2) = 0%) for therapeutic positioning of the paretic arm to 2.47 (95%CI 0.84-4.11; I(2) = 77%) for training of sitting balance. There is strong evidence that a higher dose of practice is better, with SESs ranging from 0.21 (95%CI 0.02-0.39; I(2) = 6%) for motor function of the paretic arm to 0.61 (95%CI 0.41-0.82; I(2) = 41%) for muscle strength of the paretic leg. Subgroup analyses yielded significant differences with respect to timing poststroke for 10 interventions. Neurological treatment approaches to training of body functions and activities showed equal or unfavorable effects when compared to other training interventions. Main limitations of the present review are not using individual patient data for meta-analyses and absence of correction for multiple testing.

CONCLUSIONS

There is strong evidence for PT interventions favoring intensive high repetitive task-oriented and task-specific training in all phases poststroke. Effects are mostly restricted to the actually trained functions and activities. Suggestions for prioritizing PT stroke research are given.

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. The secondary aims were to determine the effects of training on physical fitness, mobility, physical function, quality of life, mood, and incidence of adverse events.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched January 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 12: searched January 2013), MEDLINE (1966 to January 2013), EMBASE (1980 to January 2013), CINAHL (1982 to January 2013), SPORTDiscus (1949 to January 2013), and five additional databases (January 2013). 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, with no intervention, a non-exercise intervention, or usual care in stroke survivors.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed quality, and extracted data. We analysed data using random-effects meta-analyses. Diverse outcome measures limited the intended analyses.

MAIN RESULTS

We included 45 trials, involving 2188 participants, which comprised cardiorespiratory (22 trials, 995 participants), resistance (eight trials, 275 participants), and mixed training interventions (15 trials, 918 participants). Nine deaths occurred before the end of the intervention and a further seven at the end of follow-up. No dependence data were reported. Diverse outcome measures made data pooling difficult. Global indices of disability show a tendency to improve after cardiorespiratory training (standardised mean difference (SMD) 0.37, 95% confidence interval (CI) 0.10 to 0.64; P = 0.007); benefits at follow-up and after mixed training were unclear. There were insufficient data to assess the effects of resistance training.Cardiorespiratory training involving walking improved maximum walking speed (mean difference (MD) 7.37 metres per minute, 95% CI 3.70 to 11.03), preferred gait speed (MD 4.63 metres per minute, 95% CI 1.84 to 7.43), walking capacity (MD 26.99 metres per six minutes, 95% CI 9.13 to 44.84), and Berg Balance scores (MD 3.14, 95% CI 0.56 to 5.73) 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), walking capacity (MD 41.60 metres per six minutes, 95% CI 25.25 to 57.95), and also pooled balance scores but the evidence is weaker (SMD 0.26 95% CI 0.04 to, 0.49). Some mobility benefits also persisted at the end of follow-up. The variability and trial quality hampered the assessment of the reliability and generalisability of the observed results.

AUTHORS' CONCLUSIONS

The effects of training on death and dependence after stroke are unclear. Cardiorespiratory training reduces disability after stroke and this may be mediated by improved mobility and balance. There is sufficient evidence to incorporate cardiorespiratory and mixed training, involving walking, within post-stroke rehabilitation programs to improve the speed and tolerance of walking; improvement in balance may also occur. There is insufficient evidence to support the use of resistance training. Further well-designed trials are needed to determine the optimal content of the exercise prescription and identify long-term benefits.

Characteristics of exercise training interventions to improve cardiorespiratory fitness after stroke: a systematic review with meta-analysis

BACKGROUND

Cardiorespiratory fitness is low after stroke. Improving fitness has the potential to improve function and reduce secondary cardiovascular events.

OBJECTIVE

. This review with meta-analysis aims to identify characteristics and determine the effectiveness of interventions to improve cardiorespiratory fitness after stroke.

METHODS

A systematic search and review with meta-analysis was undertaken. Key inclusion criteria were the following: peer-reviewed articles published in English, adult stroke survivors, an intervention with the potential to improve cardiorespiratory fitness, and peak oxygen consumption (VO2peak) assessed preintervention and postintervention via a progressive aerobic exercise test.

RESULTS

From 3209 citations identified, 28 studies were included, reporting results for 920 participants. Studies typically included chronic, ambulant participants with mild to moderate deficits; used an aerobic or mixed (with an aerobic component) intervention; and prescribed 3 sessions per week for 30 to 60 minutes per session at a given intensity. Baseline VO2peak values were low (8-23 mL/kg/min). Meta-analysis of the 12 randomized controlled trials demonstrated overall improvements in VO2peak of 2.27 (95% confidence interval = 1.58, 2.95) mL/kg/min postintervention. A similar 10% to 15% improvement occurred with both aerobic and mixed interventions and in shorter (≤ 3 months) and longer (>3 months) length programs. Only 1 study calculated total dose received and only 1 included long-term follow-up.

CONCLUSIONS

The results demonstrate that interventions with an aerobic component can improve cardiorespiratory fitness poststroke. Further investigation is required to determine effectiveness in those with greater impairment and comorbidities, optimal timing and dose of intervention, whether improvements can be maintained in the longer term, and whether improved fitness results in better function and reduced risk of subsequent cardiovascular events.

Cardiorespiratory Fitness after Stroke: A Systematic Review

Cardiorespiratory fitness programs are increasingly used in stroke rehabilitation. Maximal oxygen uptake is the gold standard measurement of cardiorespiratory fitness; however, no recent publications have collated evidence about maximal oxygen uptake levels following stroke. We therefore performed a systematic review of maximal oxygen uptake in stroke survivors, aiming to observe changes in levels over time, and associations with severity of stroke. We searched Medline and Embase until April 2011, and included cross-sectional studies, longitudinal studies, and baseline data from intervention trials. Studies had to recruit at least 10 stroke survivors, and report direct measurement of maximal/peak oxygen uptake. We then compared maximal oxygen uptake with published data from age and gender-matched controls. The search identified 3357 articles. Seventy-two full texts were retrieved, of which 41 met the inclusion criteria. Time since stroke ranged from 10 days to over seven-years. Peak oxygen uptake ranged from 8 to 22 ml/kg/min, which was 26–87% of that of healthy age- and gender-matched individuals. Stroke severity was mild in most studies. Three studies reported longitudinal changes; there was no clear evidence of change in peak oxygen uptake over time. Most studies recruited participants with mild stroke, and it is possible that cardiorespiratory fitness is even more impaired after severe stroke. Maximal oxygen uptake might have been overestimated, as less healthy and older stroke survivors may not tolerate maximal exercise testing. More studies are needed describing mechanisms of impaired cardiorespiratory fitness and longitudinal changes over time to inform the optimal ‘prescription’ of cardiorespiratory fitness programs for stroke survivors.

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. The secondary aims were to determine the effects of training on physical fitness, mobility, physical function, quality of life, mood, and incidence of adverse events.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched April 2010), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, July 2010), MEDLINE (1966 to March 2010), EMBASE (1980 to March 2010), CINAHL (1982 to March 2010), SPORTDiscus (1949 to March 2010), and five additional databases (March 2010). 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, with no intervention, a non-exercise intervention, or usual care in stroke survivors.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed quality, and extracted data. We analysed data using random-effects meta-analyses. Diverse outcome measures limited the intended analyses.

MAIN RESULTS

We included 32 trials, involving 1414 participants, which comprised cardiorespiratory (14 trials, 651 participants), resistance (seven trials, 246 participants), and mixed training interventions (11 trials, 517 participants). Five deaths were reported at the end of the intervention and nine at the end of follow-up. No dependence data were reported. Diverse outcome measures made data pooling difficult. The majority of the estimates of effect were not significant. Cardiorespiratory training involving walking improved maximum walking speed (mean difference (MD) 8.66 metres per minute, 95% confidence interval (CI) 2.98 to 14.34), preferred gait speed (MD 4.68 metres per minute, 95% CI 1.40 to 7.96) and walking capacity (MD 47.13 metres per six minutes, 95% CI 19.39 to 74.88) at the end of the intervention. These training effects were retained at the end of follow-up. Mixed training, involving walking, increased preferred walking speed (MD 2.93 metres per minute, 95% CI 0.02 to 5.84) and walking capacity (MD 30.59 metres per six minutes, 95% CI 8.90 to 52.28) but effects were smaller and there was heterogeneity amongst the trial results. There were insufficient data to assess the effects of resistance training. The variability in the quality of included trials hampered the reliability and generalizability of the observed results.

AUTHORS' CONCLUSIONS

The effects of training on death, dependence, and disability after stroke are unclear. There is sufficient evidence to incorporate cardiorespiratory training involving walking within post-stroke rehabilitation programmes to improve speed, tolerance, and independence during walking. Further well-designed trials are needed to determine the optimal exercise prescription and identify long-term benefits.

Exercise and executive function in individuals with chronic stroke: a pilot study

BACKGROUND AND PURPOSE

Emerging evidence suggests that exercise may improve cognitive function in older adults. The purpose of this pilot study was to describe changes in measures of cognition and executive function in individuals with chronic stroke following participation in aerobic and strengthening exercise.

METHODS

A single-group, pretest-posttest design was used. Nine individuals with chronic stroke (mean age = 63.7 ± 9.1 years, mean time since stroke = 50.4 ± 37.9 months) completed a 12-week program of aerobic and strengthening exercise, 3 days per week. The primary outcome measures examined executive function (Digit Span Backwards and Flanker tests). Secondary measures examined various aspects of aerobic fitness (VO2peak and 6-minute walk distance) and function (Fugl-Meyer and 10-m walk speed).

RESULTS

Following the intervention, significant improvements were found in the Digit Span Backwards test (mean change = 0.56 ± 0.9 digits; P = 0.05), Fugl-Meyer score (mean change = 3.6 ± 5.7; P = 0.05), and Stroke Impact Scale total score (mean change = 33.8 ± 38.5; P = 0.02). A significant correlation was found between improved aerobic capacity and improved performance on the Flanker test (r = 0.74; P = 0.02).

DISCUSSION

The results of this study indicate that a 12-week aerobic and strengthening exercise program was associated with improvements in selected measures of executive function and functional capacity in people with stroke. Limitations of this study include the small sample size and lack of a comparison group.

CONCLUSIONS

This pilot study contributes to the emerging evidence that exercise improves cognition in people with stroke. These benefits indicate the need for future study with a larger group to have sufficient power to further explore these relationships.

Aerobic exercise training programmes for improving physical and psychosocial health in adults with Down syndrome

BACKGROUND

Although physical fitness has been suggested to improve physical and psychosocial health for a variety of population profiles, there is a lack of information about the safety and effectiveness of aerobic exercise for adults with Down syndrome.

OBJECTIVES

To evaluate the effectiveness and safety of aerobic exercise training programmes for physiological and psychosocial outcomes in adults with Down syndrome.

SEARCH STRATEGY

The following electronic databases were searched: The Cochrane Central Register of Controlled Trials (CENTRAL) (2009, Issue 1); MEDLINE (1966 to August 2009); EMBASE (1980 to August 2009); CINAHL (1982 to August 2009); LILACS (1982 to August 2009); PsycINFO (1887 to August 2009); ERIC (1966 to August 2009); Current Controlled Trials (August 2009); and Campbell Collaboration's Social, Psychological, Educational and Criminological Register (C2- SPECTR) (to August 2009). Information about ongoing clinical trials was sought by searching ClinicalTrials.gov (http://clinicaltrials.gov) (accessed August 2009), and the National Research Register (NRR) (2009 Issue 1).

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials using supervised aerobic exercise training programmes with behavioral components accepted as co-interventions.

DATA COLLECTION AND ANALYSIS

Two reviewers selected relevant trials, assessed methodological quality and extracted data. Where appropriate, data were pooled using meta-analysis with a random-effects model. Positive values favour the intervention group, while negative values favour the control group.

MAIN RESULTS

Three studies included in this systematic review used different kinds of aerobic activity: walking/jogging and rowing training and included participants with a broad age range (17 to 65 years). They were conducted in the USA, Portugal and Israel. In the meta-analyses, only maximal treadmill grade was improved after aerobic exercise training programmes (4.26 grades (%) [95% CI 2.06, 6.45]). Other variables relative to work performance that could not be combined in a meta-analysis were also improved in the intervention group (maximal test time P=0.0003), total turns of fan wheel (P=0.02), resistance of ergometer (p=0.003), power knee extension and flexion (p<0.00001), and timed up and go test (p=0.008). Thirty other outcomes measured in this review including, oxidative stress and body composition variables, could not be combined in the meta-analysis. Apart from work performance, trials reported no statistically significant improvements.

AUTHORS' CONCLUSIONS

There is insufficient evidence to demonstrate that there is improvement in physical or psychosocial outcomes of aerobic exercise in adults with Down syndrome. Although evidence exists to support improvements in physiological and psychological aspects from strategies using mixed physical activity programmes, well-conducted research examining long-term physical outcomes, adverse effects, psychosocial outcomes and costs is required before informed practice decisions can be made.

Physical fitness training for stroke patients

BACKGROUND

Physical fitness is low after stroke. It is unknown whether improving physical fitness after stroke reduces disability.

OBJECTIVES

To determine whether fitness training (cardiorespiratory or strength, or both) after stroke reduces death, dependence and disability. The secondary aims were to determine the effects of fitness training on physical fitness, mobility, physical function, health status and quality of life, mood and incidence of adverse events.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register (last searched March 2009), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 1, 2007), MEDLINE (1966 to March 2007), EMBASE (1980 to March 2007), CINAHL (1982 to March 2007), and six additional databases to March 2007. We handsearched relevant journals and conference proceedings, and screened bibliographies. We searched trials registers and contacted experts in the field.

SELECTION CRITERIA

We included randomised controlled trials if the aim of the intervention was to improve muscle strength or cardiorespiratory fitness, or both, and if the control groups comprised either no intervention, usual care or a non-exercise intervention.

DATA COLLECTION AND ANALYSIS

Two review authors determined trial eligibility and quality. One review author extracted outcome data at end of intervention and follow-up scores, or as change from baseline scores. Diverse outcome measures limited the intended analysis.

MAIN RESULTS

We included 24 trials, involving 1147 participants, comprising cardiorespiratory (11 trials, 692 participants), strength (four trials, 158 participants) and mixed training interventions (nine trials, 360 participants). Death was infrequent at the end of the intervention (1/1147) and follow up (8/627). No dependence data were reported. Diverse disability measures made meta-analysis difficult; the majority of effect sizes were not significant. Cardiorespiratory training involving walking, improved maximum walking speed (mean difference (MD) 6.47 metres per minute, 95% confidence interval (CI) 2.37 to 10.57), walking endurance (MD 38.9 metres per six minutes, 95% CI 14.3 to 63.5), and reduced dependence during walking (Functional Ambulation Categories MD 0.72, 95% CI 0.46 to 0.98). Current data include few strength training trials, and lack non-exercise attention controls, long-term training and follow up.

AUTHORS' CONCLUSIONS

The effects of training on death, dependence and disability after stroke are unclear. There is sufficient evidence to incorporate cardiorespiratory training, involving walking, within post-stroke rehabilitation in order to improve speed, tolerance and independence during walking. Further trials are needed to determine the optimal exercise prescription after stroke and identify any long-term benefits.

WITHDRAWN: Aerobic exercise training programmes for improving physical and psychosocial health in adults with Down syndrome

BACKGROUND

Although physical fitness has been suggested to improve physical and psychosocial health for a variety of population profiles, there is a lack of information about the safety and effectiveness of aerobic exercise for adults with Down syndrome.

OBJECTIVES

To evaluate the effectiveness and safety of aerobic exercise training programmes for physiological and psychosocial outcomes in adults with Down syndrome.

SEARCH STRATEGY

Search terms and synonyms for "aerobic exercise" and "Down syndrome" were used within the following databases: CENTRAL (2007, Issue 1); MEDLINE via PUBMED (1966 to March 2007); EMBASE (2005 to April 2007); CINAHL (1982 to March 2007); LILACS (1982 to March 2007); PsycINFO (1887 to March 2007); ERIC (1966 to March 2007); CCT (March 2007); Academic Search Elite (to March 2007), C2- SPECTR (to March 2007 ), NRR (2007 Issue 1), ClinicalTrials.gov (accessed March 2007) and within supplements of Medicine and Science in Sports and Exercise.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials using supervised aerobic exercise training programmes with behavioral components accepted as co-interventions.

DATA COLLECTION AND ANALYSIS

Two reviewers selected relevant trials, assessed methodological quality and extracted data. Where appropriate, data was pooled using meta-analysis with a random effects model

MAIN RESULTS

The two studies included in this trial used different kinds of aerobic activity: walking/jogging and rowing training. One included study was conducted in the USA, the other in Portugal. In the meta-analyses, only maximal treadmill grade, a work performance variable, was improved in the intervention group after aerobic exercise training programmes (-4.26 [95% CI -6.45, -2.06]) grade. The other outcomes in the meta-analysis showed no significant differences between intervention and control groups, as expressed by weighted mean difference: VO(2) peak -0.30 (95% CI -377, 3.17) mL.Kg.min(-1); peak heart rate, -2.84 (95% CI -10.73, 5.05) bpm; respiratory exchange ratio, 0.01 (95% CI -0.04, 0.06); pulmonary ventilation, -5.86 (95% CI -16.06, 4.34) L.min(-1). 30 other measures including work performance, oxidative stress and body composition variables could not be combined in the meta-analysis. Apart from work performance, trials reported no significant improvements in these measures.

AUTHORS' CONCLUSIONS

There is insufficient evidence to support improvement in physical or psychosocial outcomes of aerobic exercise in adults with Down syndrome. Although evidence exists which supports improvements in physiological and psychological aspects from strategies using mixed physical activity programmes, well-conducted research which examines long-term physical outcomes, adverse effects, psychosocial outcomes and costs are required before informed practice decisions can be made.

The use of aerobic exercise training in improving aerobic capacity in individuals with stroke: a meta-analysis

OBJECTIVE

To determine whether aerobic exercise improves aerobic capacity in individuals with stroke.

DESIGN

A systematic review of randomized controlled trials. DATABASES SEARCHED: MEDLINE, CINAHL, EMBASE, Cochrane Database of Systematic Reviews and Physiotherapy Evidence Database were searched.

INCLUSION CRITERIA

Design: randomized controlled trials (RCTs).

PARTICIPANTS

individuals with stroke.

INTERVENTIONS

aerobic exercise training aimed at improving aerobic capacity.

OUTCOMES

PRIMARY OUTCOMES

aerobic capacity (peak oxygen consumption (VO2), peak workload).

SECONDARY OUTCOMES

walking velocity, walking endurance.

DATA ANALYSIS

The methodological quality was assessed by the PEDro scale. Meta-analyses were performed for all primary and secondary outcomes.

RESULTS

Nine articles (seven RCTs) were identified. The exercise intensity ranged from 50% to 80% heart rate reserve. Exercise duration was 20-40 min for 3-5 days a week. The total number of subjects included in the studies was 480. All studies reported positive effects on aerobic capacity, regardless of the stage of stroke recovery. Meta-analysis revealed a significant homogeneous standardized effect size (SES) in favour of aerobic exercise to improve peak VO2 (SES 0.42; 95% confidence interval (CI) 0.15-0.69; P=0.001) and peak workload (SES 0.50; 95% CI 0.26-0.73; P<0.001). There was also a significant homogeneous SES in favour of aerobic training to improve walking velocity (SES 0.26; 95% CI 0.05-0.48; P= 0.008) and walking endurance (SES 0.30; 95% CI 0.06-0.55; P= 0.008).

CONCLUSIONS

There is good evidence that aerobic exercise is beneficial for improving aerobic capacity in people with mild and moderate stroke. Aerobic exercise should be an important component of stroke rehabilitation.

A community-based upper-extremity group exercise program improves motor function and performance of functional activities in chronic stroke: a randomized controlled trial

OBJECTIVE

To assess the effects of a community-based exercise program on motor recovery and functional abilities of the paretic upper extremity in persons with chronic stroke.

DESIGN

Randomized controlled trial.

SETTING

Rehabilitation research laboratory and a community hall.

PARTICIPANTS

A sample of 63 people (> or =50y) with chronic deficits resulting from stroke (onset > or =1y).

INTERVENTIONS

The arm group underwent an exercise program designed to improve upper-extremity function (1h/session, 3 sessions/wk for 19wk). The leg group underwent a lower-extremity exercise program.

MAIN OUTCOME MEASURES

The Wolf Motor Function Test (WMFT), Fugl-Meyer Assessment (FMA), hand-held dynamometry (grip strength), and the Motor Activity Log.

RESULTS

Multivariate analysis showed a significant group by time interaction (Wilks lambda=.726, P=.017), indicating that overall, the arm group had significantly more improvement than the leg group. Post hoc analysis demonstrated that gains in WMFT (functional ability) (P=.001) and FMA (P=.001) scores were significantly higher in the arm group. The amount of improvement was comparable to other novel treatment approaches such as constraint-induced movement therapy or robot-aided exercise training previously reported in chronic stroke. Participants with moderate arm impairment benefited more from the program.

CONCLUSIONS

The pilot study showed that a community-based exercise program can improve upper-extremity function in persons with chronic stroke. This outcome justifies a larger clinical trial to further assess efficacy and cost effectiveness.

Aerobic exercise training programmes for improving physical and psychosocial health in adults with Down syndrome

BACKGROUND

Although physical fitness has been suggested to improve physical and psychosocial health for a variety of population profiles, there is a lack of information about the safety and effectiveness of aerobic exercise for adults with Down syndrome.

OBJECTIVES

To evaluate the effectiveness and safety of aerobic exercise training programmes for physiological and psychosocial outcomes in adults with Down syndrome.

SEARCH STRATEGY

Search terms and synonyms for "aerobic exercise" and "Down syndrome" were used within the following databases:CENTRAL (2005, Issue 2); MEDLINE (1966 to March 2005); EMBASE (2005 to April 2005); CINAHL (1982 to March 2005); LILACS (1982 to March 2005); PsycINFO (1887 to March 2005); ERIC (1966 to March 2005); CCT (March 2005); Academic Search Elite (to March 2005), C2- SPECTR (to March 2005 ), NRR (2005 Issue 1), ClinicalTrials.gov (accessed March 2005)and within supplements of Medicine and Science in Sports and Exercise.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials using supervised aerobic exercise training programmes with behavioral components accepted as co-interventions.

DATA COLLECTION AND ANALYSIS

Two reviewers selected relevant trials, assessed methodological quality and extracted data. Where appropriate, data was pooled using meta-analysis with a random effects model

MAIN RESULTS

The two studies included in this trial used different kinds of aerobic activity: walking/jogging and rowing training. One included study was conducted in the USA, the other in Portugal. In the meta-analyses, only maximal treadmill grade, a work performance variable, was improved in the intervention group after aerobic exercise training programmes (-4.26 [95% CI -6.45, -2.06]) grade. The other outcomes in the meta-analysis showed no significant differences between intervention and control groups, as expressed by weighted mean difference: VO(2) peak -0.30 (95% CI -377, 3.17) mL.Kg.min(-1); peak heart rate, -2.84 (95% CI -10.73, 5.05) bpm; respiratory exchange ratio, 0.01 (95% CI -0.04, 0.06); pulmonary ventilation, -5.86 (95% CI -16.06, 4.34) L.min(-1). 30 other measures including work performance, oxidative stress and body composition variables could not be combined in the meta-analysis. Trials reported no significant improvements in these measures.

AUTHORS' CONCLUSIONS

There is insufficient evidence to support improvement in physical or psychosocial outcomes of aerobic exercise in adults with Down syndrome. Although evidence exists which supports improvements in physiological and psychological aspects from strategies using mixed physical activity programmes, well-conducted research which examines long-term physical outcomes, adverse effects, psychosocial outcomes and costs are required before informed practice decisions can be made.

Exercise-induced changes of the upper extremity in chronic stroke survivors

Problems with daily activities due to decreased aerobic capacity and decreased strength are common in people who survive a stroke. Implementation of exercise for the upper extremity is challenging because of weakness and other impairments that limit performance of exercise activities. Although maximal exercise testing protocols are difficult to administer, submaximal testing may be a safe and effective means for prescribing exercise. Research studies have demonstrated that people with stroke can improve aerobic capacity and upper extremity muscle strength with exercise intervention, although the number of randomized controlled trials is limited and this area requires further investigation.

Strength Training in Individuals with Stroke

PURPOSE: This paper reviews the mechanisms underlying the inability to generate force in individuals with stroke and summarizes the effects of strength training in these individuals. In addition, a systematic review of studies that have incorporated progressive strengthening interventions in individuals with stroke is presented. SUMMARY OF KEY POINTS: Central (e.g., motor recruitment) and peripheral (e.g., muscle atrophy) sources may alter muscle strength in individuals with stroke and further investigations are needed to partition and quantify their effects. As to the effect of strength training interventions in individuals with stroke, the majority of studies (albeit with small samples) that evaluated muscle strength as an outcome demonstrated improvements. With regard to the effect of strength training on functional outcomes in individuals with stroke, positive outcomes were found in less rigorous pre-test/post-test studies, but more conflicting results with controlled trials. CONCLUSIONS: Although there is some suggestion that strength training alone can improve muscle strength, further research is required to optimize strength training and the transfer of these strength gains to functional tasks in individuals with stroke.