Long-Term Benefit of Gastric Bypass Surgery on Fitness

This study addressed the paucity of data exploring long-term effects of metabolic and bariatric surgery (MBS)-related weight loss on fitness.

Data from MBS patients (SURG; n = 82) and comparable non-surgery participants (NSURG; n = 88) were collected from a subset of a prospective trial, the Utah Obesity Study. Fitness was assessed through maximal and submaximal treadmill tests using a modified Bruce protocol. Submaximal exercise tests were performed preceding surgery at baseline and 11.5 years later. A subset (n = 97) of the 170 participants also performed maximal treadmill tests 2 and 6 years after baseline. Weight and BMI were recorded at each visit. Between-group treadmill time comparisons were adjusted for sex and weight.

As expected, SURG had lower BMI and weight than NSURG at all follow-up visits (p < 0.0001). Treadmill time, adjusted for sex, baseline treadmill time, and weight over the 11.5-year period, was elevated in surgery compared to non-surgery groups at all follow-up visits (p < 0.01), but the fitness advantage gradually decreased over time.

An initially dramatic fitness benefit achieved with weight loss in MBS patients gradually declined but remained higher than non-surgery counterparts beyond a decade. An emphasis on physical activity may help sustain improved fitness after bariatric surgery.