Physical Activity and Protein Supplementation After Bariatric Surgery (PAPAB)

Bariatric surgery has become a major treatment option for severe obesity in adults. Despite the advantages of bariatric surgery, attention needs to be paid to the possible risks following the surgical treatment. Postoperative risks include protein deficiency and pronounced muscle mass loss. Indeed, numerous studies indicate a significant reduction in lean body mass resulting from protein deficiency after bariatric surgery.

Dietary proteins have shown to play an important role in body weight regulation. A protein-rich diet attains satiety and thereby facilitates reduction in overall energy intake. It has also shown to enhance food-induced thermogenesis. Furthermore, a protein-rich diet - ideally in combination with exercise - preserves lean body mass and thus resting energy expenditure leading to an improvement of long-term energy balance. Therefore, protein-rich diets or protein supplements, respectively, might facilitate weight loss, especially body fat loss and protect against loss in muscle mass in patients who underwent bariatric surgery. The aim of the present randomized, placebo-controlled, double blind pilot study was to test the possible benefit of proteins in combination with exercise in patients undergoing bariatric surgery, and to examine, whether computer-assisted exercise is advantageous when comparing it to a usual exercise program using written exercise instructions. Therefore, we study the influence of postoperative protein supplementation in combination with computer-assisted exercise on body composition changes, and body weight reduction, as well as physical fitness, protein status and muscle function in obese patients after bariatric surgery.

Inclusion criteria

• Age of 18 - 65 years
• Body weight of ≤ 150 kg
• BMI > 35 kg/m2
• Indication for laparoscopic sleeve gastrectomy and laparoscopic Roux-en-Y gastric bypass. The decision about the type of surgery is performed independent of the study by the surgeons in charge according to the German S3 guideline.

Exclusion criteria

• Kidney diseases of any kind
• Serious gastrointestinal diseases (e.g. Morbus Crohn, Colitis Ulcerosa, etc.)
• Serious musculoskeletal diseases
• Serious heart diseases (Myocardial infarction, stent implantation, stroke, etc.)
• Intake of blood thinning medicine (e.g. ASS, Marcumar, etc.)