Impact of deep water running in interval training (DWR-IT) on body composition, functional capacity, and quality of life in overweight adults: study protocol for a randomized controlled trial

BACKGROUND: Interval training in deep water running (DWR-IT) is a training method to improve cardiovascular fitness, functional health, and quality of life and to help control body weight. Its main advantages are the reduction of joint overload and a low risk of musculoskeletal injuries. The aim of the study is to investigate the influence of DWR-IT on functional capacity, body composition, and quality of life of overweight middle-aged adults. METHODS: This is a randomized controlled, two-arm, open, parallel clinical trial with overweight adults. Volunteers will be allocated to a water group (WG), which will be submitted to the intervention, or a control group, which will not be subjected to any kind of intervention. The evaluation will be composed of anamnesis, electrical bioimpedance, six-minute walk test (6MWT), questionnaire on the Impact of Weight on Quality of Life-lite (IWQOL-LITE), Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, chair stand test, arm curl test, and food frequency questionnaire. The DWR-IT will last for 12 weeks, systematically increasing the intensity and training volume. DISCUSSION: The objective of this clinical trial is to evaluate the effect of DWR-IT on overweight adults. The study is guided through practice based on scientific evidence for the use of training and aquatic rehabilitation. It is expected that after 12 weeks of aquatic intervention there will be a decrease in body fat by about 10%, evaluated by electrical bioimpedance, an increase of about 25% of cardiorespiratory endurance, evaluated by 6MWT, and an improvement of about 25% of physical function domains, self-esteem, distress in public places, and work, analyzed by IWQOL-LITE in the WG. TRIAL REGISTRATION: The study protocol was published in the Brazilian Registry of Clinical Trials (ReBEC) on June 16, 2016. Registration number: RBR-6dmh7d. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s13063-019-3618-7) contains supplementary material, which is available to authorized users.