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Updated: May 21, 2026

Roux-en-Y Gastric Bypass Operation in Rats
Published on: June 11, 2012
Effects of aerobic exercise training on variability and heart rate kinetic during submaximal exercise after gastric
Viviane Castello-Simões1, Rodrigo Polaquini Simões, Thomas Beltrame
1Cardiopulmonary Physiotherapy Laboratory, Nucleus of Research in Physical Exercise, Federal University of São Carlos, São Carlos, São Paulo, Brazil. vivica_castello@yahoo.com.br
Background:
This study aimed to determine whether morbidly obese women have an alteration of heart rate (HR) kinetics and HR variability (HRV) during the 6-min walk test (6MWT) and if an aerobic exercise training can modify these indexes after gastric bypass surgery (GBS).
Design And Methods:
Nineteen morbidly obese women were randomized to a trained (TG) or control group and 12 women of eutrophic group (EG) were also evaluated. The obese women were tested on two occasions: 1 week before and 4 months after GBS through record of HR and R-R intervals during 6MWT for analysis HR kinetics. The TG underwent an aerobic exercise training program on a treadmill (1-h session, totaling 36 sessions over 12-week).
Results:
Both obese groups demonstrated a significant reduction of rMSSD and slower HR kinetics during the 6MWT when compared to the EG. In addition, only the TG demonstrated a significant improvement in HRV indexes, walking distance, faster time constant and mean response time of HR during 6MWT after training (p < 0.05).
Conclusion:
Morbidly obese women have slower HR kinetics and altered cardiac modulation during submaximal exercise. However, aerobic exercise training can produce beneficial adaptations in HRV and faster HR kinetics following GBS.
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