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Updated: Feb 16, 2026

Roux-en-Y Gastric Bypass Operation in Rats
Published on: June 11, 2012
Changes in Physical Activities and Body Composition after Roux-Y Gastric Bypass Surgery
Alex Harley Crisp1, Rozangela Verlengia2, Michele Novaes Ravelli3
1Programa de Pós-Graduação de Alimentos e Nutrição-Ciências Nutricionais, Universidade Estadual Paulista (UNESP), Araraquara, SP, Brazil. alexhcrisp@gmail.com.
Purpose:
Given the importance of physical activities for health outcomes, it is still unclear whether bariatric surgery per se and the standard care after surgery would result in an increase of physical activity level. This study aimed to determine physical activities preoperatively and at 6 and 12 months postoperatively among female patients who underwent bariatric surgery, and to investigate its relationship with body composition changes.
Material And Methods:
Thirty-four women who had Roux-Y gastric bypass (RYGB) surgery completed the study. Physical activity was measured objectively for 7 consecutive days by using an ActiGraph GT3X+ accelerometer. Body composition was estimated by using multifrequency bioimpedance analysis.
Results:
The percentage of time spent in moderate-to-vigorous physical activity (MVPA) changed significantly from preoperatively to 6 months postoperatively; however, no difference was observed at 12 months. No significant changes were detected for other physical activity variables. Multivariable regression analysis suggested that the percentage of time spent in sedentary activity was associated with fat-free mass loss at 6 months (β = - 0.323; 95% CI = - 0.649 to 0.003) and 12 months (β = - 0.510; 95% CI = - 0.867 to - 0.154) postoperatively.
Conclusion:
The overall MVPA increased at 6 months post-RYGB surgery; however, this change was not maintained at 12 months. Despite the considerable body mass loss postoperatively, most of the subjects were classified as being physically inactive and did not change their sedentary behavior. These findings indicate that female patients undergoing bariatric surgery should be encouraged to increase their physical activity level.
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