Comparison of linear periodized and non-periodized combined training in health markers and physical fitness of adults with obesity: Clinical trial protocol

The literature discusses that combined training, aerobic more resistance exercises in the same session, is a suitable strategy for people with obesity and that exercise periodization leads to positive health outcomes; however, the implication of different periodizations of combined training for health outcomes in obese adults requires further investigation. The aim of the study will be to describe the methodology used to compare the effect of linear periodized and non-periodized combined training on health markers and health-related physical fitness in adults with obesity. This is a blinded randomized controlled clinical trial investigating adults with obesity in the age group 20–50 years. The sample will be non-probabilistic, and participants will be allocated randomly into one of three groups: control group (CG), non-periodized group (NG), and periodized group (PG). The intervention will occur in 60-min sessions, 3 days a week for 16 weeks, with 1 week dedicated to familiarization with the training and 15 weeks of combined training (aerobic followed by resistance in the same session). The PG group will perform three mesocycles of 5 weeks each, progressing in intensity throughout the intervention [aerobic: from 40-49% to 60–69% of heart rate reserve (HRR); strength: from 12 to 14 maximum repetitions (MR) to 8 to 10MR]; the NG group will maintain the same relative intensity throughout the study (aerobic: 50–59% of HRR; strength: 2 sets of 10–12 MR). Participants in the CG group will maintain their usual activities without the proposed intervention. Pre- and post-intervention assessments will be performed for biochemical markers, body composition, cardiovascular parameters, cardiorespiratory fitness, maximum upper and lower limb strength, flexibility, and subjective health-related parameters. This project was approved by the Committee of Ethics and Research with Human Beings of the institution of origin (protocol 2,448,674) and registered in the Brazilian Registry of Clinical Trials (RBR-3c7rt3).