The World Health Organization defines stroke as “rapidly developing clinical signs of focal or global disturbance of cerebral function, lasting more than 24 hours or leading to death with no apparent cause other than that of vascular origin.” It is the second leading cause of death worldwide; its burden is the second heaviest for the number of years lost due to ill-health, and about half of stroke survivors suffer from long-term disability. After stroke, patients experience impaired muscle function with consequent loss of movement and independence in daily activities. In addition to hemiparesis, inactivity by itself has negative effects on muscle power and strength and ultimately on individual independence. In this scenario, rehabilitation aims to improve functional ability as well as psychological status and quality of life. In particular, physical-fitness training interventions play a key role in reducing fatigue and risk of falls and fracture, while also improving global cognitive function, mood, independence in activities of daily living (ADLs), and quality of life. Moreover, modern concepts of rehabilitation favor repetitive, task-specific practice such as fitness training to exploit mechanisms of neuroplasticity, modeling the brain to produce better functional outcomes. Additionally,cardiorespiratory and resistance training can be beneficial in the secondary prevention of stroke, reducing comorbidity.
This review investigated whether physical fitness training, in terms of cardiorespiratory, resistance, and/or mixed training, are effective in improving health and functioning in people previously affected by stroke.
This review is important for
People who had a stroke and have trouble in fulfilling daily activities, their loved ones/caregivers, health professionals caring for this population, general practitioners, researchers, and policymakers.
Outcomes of this review
This is an update of Cochrane Systematic Reviews (CSRs) published in 2004, 2009, 2011, 2013, and 2016. The outcomes analyzed were death from all causes, death or dependence, disability, physical fitness (peak VO2), adverse events, vascular risk factors, mobility (walking speed/capacity), physical function (balance), mood and cognition, and quality of life.
The CSR included 75 trials, published and/or registered up to July 2018, with 3,017 participants. Results showed that,for people with stroke, cardiorespiratory training (CT), resistance training (RT), or mixed training (MT) may make no difference on mortality compared to control at the end of intervention and at the end of follow-up. CT probably improves and MT may improve disability scores compared to control at the end of intervention. CT probably leads to better physical fitness (VO2 peak) and physical function (balance) and improves mobility compared to control at the end of intervention. There may be a 7% decrease in stroke hospitalization due to improvement in cardiorespiratory fitness. RT may improve balance, and MT may improve both balance and mobility, compared to control at the end of intervention.
To sum up, it is likely that cardiorespiratory training together with walking would be the most beneficial training for people with stroke. There was not enough evidence to conclude that fitness training can be effective on quality of life, mood, or cognition. No evidence was found that any type of fitness training caused harm, so it appears to be safe.
These results must be interpreted with caution because (i) there are different scales assessing disability, and this raises the problem of the validity of results when combined; (ii) in some trials the duration of the intervention was not equivalent for the control groups; and (iii) only a few studies included non-walking patients, so it is not entirely possible to generalize the results for those patients.
Author’s conclusion of the review
Fitness training overall may make little or no difference in occurrence of death from all causes, suggesting that exercise is safe, but at the same time the authors could not determine whether exercise reduces mortality or the chance of death or dependency. Cardiorespiratory training probably slightly reduces disability. Similarly, mixed training may produce the same result. This beneficial effect on disability could be attributable to increased mobility and balance. There is enough evidence to support the inclusion of cardiorespiratory, mixed training, and walking activity within post-stroke rehabilitation programs to improve the aforementioned outcomes. Even though cognitive function was considered to be a fundamental outcome of interest for stroke patients, the intervention’s effect on cognitive function still remains to be thoroughly investigated.
The authors recommend that large-scale clinical studies are needed. They should (a) adhere to CONSORT guidelines for clinical trials; (b) follow reporting guidelines for the interventions; and (c) include a larger population of stroke patients. Future studies should aim to find out: (i) the ideal duration and frequency of physical fitness training; (ii) its effect on depression, fatigue, and cognition; and (iii) post-intervention long-term effects.
Comment by Sara Liguori