Physical activity and risk of infection, severity and mortality of COVID-19: a systematic review and non-linear dose–response meta-analysis of data from 1 853 610 adults
Yasmin Ezzatvar, Robinson Ramírez-Vélez, Mikel Izquierdo, Antonio Garcia-Hermoso
British Journal of Sports Medicine, doi:10.1136/bjsports-2022-105733
Objective To quantify the association between physical activity and risk of SARS-CoV-2 infection, COVID-19associated hospitalisation, severe illness and death due to COVID-19 in adults. Design A systematic review and meta-analysis. Data sources Three databases were systematically searched through March 2022. Eligibility criteria for selecting studies Peerreviewed articles reporting the association between regular physical activity and at least one COVID-19 outcome in adults were included. Risk estimates (ORs, relative risk (RR) ratios or HRs) were extracted and pooled using a random-effects inverse-variance model. Results Sixteen studies were included (n=1 853 610). Overall, those who engaged in regular physical activity had a lower risk of infection (RR=0.89; 95% CI 0.84 to 0.95; I 2 =0%), hospitalisation (RR=0.64; 95% CI 0.54 to 0.76; I 2 =48.01%), severe COVID-19 illness (RR=0.66; 95% CI 0.58 to 0.77; I 2 =50.93%) and COVID-19-related death (RR=0.57; 95% CI 0.46 to 0.71; I 2 =26.63%) as compared with their inactive peers. The results indicated a non-linear dose-response relationship between physical activity presented in metabolic equivalent of task (MET)-min per week and severe COVID-19 illness and death (p for non-linearity <0.001) with a flattening of the dose-response curve at around 500 MET-min per week. Conclusions Regular physical activity seems to be related to a lower likelihood of adverse COVID-19 outcomes. Our findings highlight the protective effects of engaging in sufficient physical activity as a public health strategy, with potential benefits to reduce the risk of severe COVID-19. Given the heterogeneity and risk of publication bias, further studies with standardised methodology and outcome reporting are now needed. PROSPERO registration number CRD42022313629. Contributors AG-H and YE conceptualised and designed the study, drafted the initial manuscript, and reviewed and revised the manuscript. RR-V and YE designed the data collection instruments, collected data, carried out the initial analyses and reviewed and revised the manuscript. MI and AG-H conceptualised and designed the study, coordinated and supervised data collection, and critically reviewed the manuscript for important intellectual content. All authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work. AG-H is responsible for the integrity of the work as a whole.
Competing interests None declared. Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.
Patient consent for publication Not applicable. Ethics approval Not applicable. Provenance and peer review Not commissioned; externally peer reviewed.
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise. Online supplemental eTable 2. Results Online supplemental eFigure 1. Doi plot for hospitalisation. Relative Risk was transferred to natural logarithm form. BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance Supplemental material placed on this supplemental material which has been supplied by the author(s)
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