Author(s): FRIEDMAN, L., GOLDENSHLUGER, A., TURJEMAN, T., SAKRAN, N., DICKER, D., KAIS, H., GOITEIN, D., KEIDAR, A., DUVNOV-RAZ, G., MHALER, I., APTERMAN, A., ISRAEL, I., GEPNER, Y., Institution: TEL AVIV UNIVERSITY , Country: ISRAEL, Abstract-ID: 1269

INTRODUCTION:
Approximately 50% of individuals experience weight regain within five years following bariatric surgery (BS). This is primarily attributed to decreased resting metabolic rate (RMR), driven by fat-free mass (FFM) loss post-BS. This study aimed to investigate the impact of exercise training on RMR and examine the association between changes in RMR and body composition after BS.
METHODS:
Sixty candidates (39.2±10.7y, 114.3±17.5kg, 41.7±4.4kg/m2) for BS were enrolled in a six-month open-label randomized controlled clinical trial. Participants were randomly assigned to one of four groups: control group (receiving standard care), aerobic, resistance, or combined online supervised training. Training sessions gradually increase to 60 minutes/session, 3 times/week. Pre- and post-intervention RMR measured by indirect calorimetry and body composition (FFM and fat mass) measured by dual-energy X-ray.
RESULTS:
The 38 participants (aerobic; n=11, strength; n=10, combined; n=11, control; n=6) that completed the study by February 2024, demonstrated a significant (p<0.01) decrease in body weight (-31.1±8.7 kg), FFM (-6.61± 2.6 kg), fat mass (-24.4±7.4 kg), and absolute-RMR (-397± 264kcal/day). Yet, all study groups demonstrated similar and significant (p<0.01) increase in RMR adjusted to body weight (2.09±2.58 kcal/kg/day). The aerobic group displayed a significant correlation between FFM loss and absolute RMR six months post-surgery (r=0.646, p<0.05). In the combined group, RMR changes were associated with both weight loss (r=0.698, p=0.01) and fat mass loss (r=0.751, p=0.01).
CONCLUSION:
Relative to body weight, RMR increased following BS with or without exercise training. Despite the notable loss of FFM, the decline in absolute RMR values following BS may not necessarily signify future weight regain.