Abstract
Background: Exercise and weight loss diets are two independent non-pharmaceutical strategies known to improve several aspects of body composition and health. We plan to systematically review randomized controlled trials investigating weight loss diets alone compared to weight loss diets in conjunction with exercise on energy intake, body weight, body composition, cardiometabolic risk factors, sex hormones, and mental health. Methods and analysis: PubMed/MEDLINE, EMBASE, ISI (Web of sciences), Scopus, and Google Scholar will be searched to retrieve potential controlled clinical trials investigating the effects of exercise in conjunction with weight-loss diets compared with weight-loss diets alone on energy intake, body weight and composition (fat mass, fat-free mass), anthropometrics (waist circumference), cardiometabolic markers, sex hormones [testosterone, estradiol, and sex hormone binding globulin (SHBG)], liver and kidney enzymes (alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), uric acid, blood urea nitrogen (BUN), and glomerular filtration rate (GFR), quality of life, and depression in adults will be included. The weighted mean difference (WMD) and its corresponding 95% confidence intervals (CIs) will be derived using the random effects model. Several subgroup analyses such as gender, age, BMI, exercise protocol, and diet used for weight loss will be conducted to explore possible sources of heterogeneity. Publication bias will be explored by inspecting funnel plots and by conducting asymmetry tests. Overall quality of the evidence will be assessed by using the NutriGrade scoring system, which is designed to judge the overall quality of meta-analyses of clinical trials conducted in the field of nutrition. Discussion: This proposed systematic review and meta-analysis aims to compare the effects of a low-calorie diet with low-calorie diet plus exercise on the risk factors for chronic diseases. We hope this systematic review and meta-analysis will provide valuable information regarding the values which exercise add to weight-loss diets. No primary data are going to be collected; therefore, ethical approval is not required. The resulting manuscripts will be disseminated in peer-reviewed journals and at international and local conferences. Systematic review registration: This protocol in being considered for registration in the International Prospective Register of Systematic Reviews (PROSPERO).
Effect of egg consumption on inflammatory markers: a systematic review and meta‐analysis of randomized controlled clinical trials
