BACKGROUND To investigate whether a text message intervention improves adherence to preoperative exercise advice prior to laparoscopic sleeve gastrectomy (LSG). METHODS A single-blinded parallel design 1:1 ratio randomized controlled trial was performed in patients undergoing LSG as a single-stage bariatric procedure for morbid obesity. The intervention group received preoperative daily text messages. The primary outcome was adherence to preoperative exercise advice as assessed by the number of participants partaking in ≥450 metabolic equivalent minutes (METmin-1 ) exercise activity per week preoperatively. RESULTS Eighty-eight patients were included in the analysis with 44 allocated to each arm. Adherence and exercise activity increased significantly from baseline in the exposure group (EG) but not in the control group (CG). Adherence was significantly higher in the EG at the end of the intervention period compared to the CG. Despite increased exercise activity, there was no improvement in 6-min walk test or surgical recovery. CONCLUSIONS A daily text message intervention improved adherence to preoperative exercise advice, but this did not correlate with improved surgical recovery.