Effect of Protein Supplementation and a Structured Physical Exercise Program on Changes in Body Composition, Metabolic Flexibility (Energy Consumption of Substrates), and Functionality in Women During Weight Loss Induced by BS

Obesity is considered a chronic disease that increases the risk of developing diseases that reduce life expectancy. The treatment of obesity is complex. However, treatments based exclusively on dietary changes have not shown long-term efficacy especially in people with severe obesity. In contrast, in this group of people bariatric surgery (BS) has shown good long-term results in weight loss and maintenance. These changes are accompanied by significant improvements in health, improved quality of life, and reduced mortality. However, the changes in the digestive system created by BS and the high level of dietary restriction, affect the nutritional status and require a proper supplementation of vitamins and minerals during the follow-up. Intense weight loss during the first few months, coupled with an insufficient amount of protein in the diet, can lead to a loss of muscle mass. Excessive muscle loss during the short-term period can lead to functional repercussions (decreased strength and physical function) and reduced calories that the body burns daily. Naturally, this is especially important in people suffering from sarcopenia before BS, and it occurs more frequently in postmenopausal women. Despite this is known, specific protein intake recommendations after BS have not yet been defined based on scientific evidence. In this context, the first part of our proposal will assess the effect of two levels of protein supplementation: standard (S-PS) versus high (H-PS) on changes in a) body composition, b) energy expenditure, c) metabolic flexibility d) the physical condition during weight loss that follows BS. In addition, in patients with H-PS, the added effect of a physical exercise program, carried out with a personal trainer (professional of sports medicine trainer) virtually, will be evaluated. Protein supplementation and the virtual exercise program will be done during the 4 months following BS, and the results will be studied at 4, 8, and 12 months. Once the results have been defined, it is essential to transfer the recommendations to the real world. In a second part, and to achieve knowledge transfer to clinical practice, the investigators will explore the key elements that influence patient experience (XPA).