Background: physical activity is increasingly recommended and offered in various healthcare systems and for a variety of health conditions because of its associated benefits of improved overall physical, mental and social health. It is therefore crucial at this stage to establish the efficacy and safety of physical activity/exercise.
Objectives: 1) to find all the available evidence from Cochrane Reviews of the effectiveness of physical activity/ exercise for various health outcomes; 2) to assess the strength and quality of the existing evidence; and 3) to create recommendations for future researchers, patients and clinicians.
Methods: we adhered to the Cochrane Handbook for Systematic Reviews of Interventions and Preferred Reporting Items for Overviews of Reviews while writing and reporting this overview. We included Cochrane Reviews of randomized controlled trials (RCTs) involving both healthy individuals and medically compromised patients of any age and gender. Only reviews assessing physical activity/exercise as a stand-alone intervention were included. Reviews evaluating any type of health-related outcome measures; and any types of controls were deemed eligible. Complex interventions assessing exercise or physical activity and diet, behavioural changes were excluded. The methodological quality of the Cochrane Reviews was independently evaluated by two reviewers using the Amstar-II tool.
Results: we included 155 Cochrane Reviews. Conditions included AIDS/HIV, angina, anxiety, asthma, cancer (and related symptoms), carpal tunnel syndrome, cerebral palsy, chronic fatigue syndrome, chronic kidney disease, chronic obstructive pulmonary disease, cognitive impairment (including dementia), coronary heart disease, critical illness, depression, Down syndrome, diabetes mellitus (gestational), dysmenorrhoea, faecal incontinence, influenza, intermittent claudication, fibromyalgia, haematological malignancies, haemophilia, meniscal damage, multiple sclerosis, nicotine dependence, osteoarthritis, overweight/obesity, pain (various syndromes and sites), peripheral neuropathy, pre‐eclampsia, rheumatoid arthritis, schizophrenia and stroke (among others). Preliminary analyses suggest that most of them were of excellent methodological quality.
Conclusions: there are a large number of Cochrane Reviews evaluating the effectiveness of physical activity/ exercise. The evidence suggests that physical activity/exercise improves health outcomes with minimal safety concerns. The overall quality of the evidence is moderate, and some methodological weaknesses have been spotted.
Patient or healthcare consumer involvement: none.