We reviewed the evidence that examines whether physical fitness training is beneficial for a range of health and function outcomes in people with stroke.
Physical fitness is important to allow people to carry out everyday activities such as walking and climbing stairs. Physical fitness varies among everyone. For example, fitness in men tends to be a little higher than in women and everyone's fitness becomes reduced as we get older and if we become less physically active. Physical fitness is often particularly low in stroke survivors. It may limit their ability to perform everyday activities and also worsen any stroke-related disability. For this reason fitness training has been proposed as a beneficial approach for people with stroke. However, taking part in fitness training could have a range of other benefits important to people with stroke such as improving cognitive function (thinking skills), improving mood, and quality of life, and it could reduce the chance of having another stroke.
By February 2015 we identified 58 trials for inclusion in the review. The trials involved at total of 2797 participants at all stages of care including being in hospital or back living at home. Most of the people who took part were able to walk on their own. The trials tested different forms of fitness training; these included 1) cardiorespiratory or 'endurance' training, 2) resistance or 'strength' training, or 3) mixed training, which is a combination of cardiorespiratory plus resistance training.
We found that cardiorespiratory fitness training, particularly involving walking, can improve exercise ability and walking after stroke. Mixed training improves walking ability and improves balance. However, there was not enough information to draw reliable conclusions about the impact of fitness training on other areas such as quality of life, mood, or cognitive function. Cognitive function is under-investigated despite being a key outcome of interest for stroke survivors. There was no evidence that any of the different types of fitness training caused injuries or other health problems; exercise appears to be a safe intervention. We need more studies to examine the benefits that are important to stroke survivors, in particular for those with more severe stroke who are unable to walk.
Quality of the evidence
Studies of fitness training can be difficult to carry out. This means most of the studies were small and of moderate quality. However, some consistent findings did emerge with different studies all tending to show the same effect.
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.
Levels of physical fitness are low after stroke. It is unknown whether improving physical fitness after stroke reduces disability.
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.
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.
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.
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.
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.