Patients and methods: This prospective study conducted between January 2016 and May 2017 included 27 patients (4 males, 23 females; mean age 37.1±10.4 years; range, 18 to 52 years) who underwent bariatric surgery and 20 healthy controls (3 males, 17 females; mean age 32.0±5.7 years; range, 26 to 46 years). All patients were evaluated by using the short form of International Physical Activity Questionnaire (IPAQ), Pittsburgh Sleep Quality Index (PSQI), Beck Depression Inventory (BDI), and short form 36 (SF-36). Patients were evaluated for regional musculoskeletal pain including back, waist, hip, knee, ankle, heel, and metatarsal pain using visual analog scale. Presence of pes planus was recorded. The examinations and tests performed in the preoperative period were repeated at postoperative six months and the results were compared with the control group.

Results: The body mass index was 46.2±5.2 kg/m² preoperatively and 33.8±5.0 kg/m² postoperatively (p<0.001). The total IPAQ was 345.4±172.8 metabolic equivalent (MET)-min/week preoperatively and 672.8±227.8 MET-min/week postoperatively (p<0.001). Pittsburgh Sleep Quality Index was 7.6±3.0 preoperatively and 3.5±2.4 postoperatively, whereas BDI was 20.2±8.5 preoperatively and 9.9±7.4 postoperatively. The results were statistically significant (p<0.001, p<0.001, respectively). A statistically significant improvement was found in all subsections of the SF-36. Pre- and postoperative results of the 27 patients were compared with those of the control group.

Conclusion: Obesity is significantly associated with joint pain, physical function impairment, depression, and sleep disorders. Significant weight loss after bariatric surgery improves functional recovery and patient's psychology in a short time. Keywords : Bariatric surgery, depression, musculoskeletal pain, obesity, physical activity, sleep