Meta analysis of randomized controlled trials examining physical activity in cancer survivors
Cancer survivors who have successfully completed their primary cancer treatment often expect to resume their work or daily life at a level similar to that before the cancer diagnosis. While cancer treatment has been shown to be effective in prolonging survival, it can be intensive and can lead to increased fatigue, decreased physical activity, and a reduction in quality of life. In addition, these unwanted effects of treatment can be prolonged and hinder the patients’ return to normal life. Physical activity is a potentially appealing intervention that could alleviate related to cancer and assist patients in returning to the health status they had before treatment. A systematic review published in 2005 summarised the evidence supporting the recommendation of physical activity during and after treatment related to cancer and a meta-analysis published in 2006 reported more favourable outcomes when physical activity was carried out after treatment. In a recent study published in 2011, starting an exercise programme after the completion of treatment was shown to be acceptable to over three quarters of patients. Several randomised controlled trials have assessed the efficacy of physical activity on indicators of physical and mental health in patients after cancer treatment, and these trials reported significant improvement after physical activity. The effects of physical activity on cancer have been examined in nine meta-analyses, with three focusing on breast cancer and six on any type of cancer. Moreover, more randomised controlled trials have been published since the publication of the last meta-analysis in 2011. We updated the most recent meta-analysis by including studies published more recently and included only randomised controlled trials. Using data from randomised controlled trials, we evaluated the best current evidence for the effects of physical activity on physical functions, physiological parameters, body composition, psychosocial outcomes, and quality of life in adult patients after they had completed their main treatment related to cancer.