Effect of exercise training after bariatric surgery: A 5-year follow-up study of a randomized controlled trial

Abstract

Background and objectives: We previously showed in a 6-month randomized controlled trial that resistance training and protein supplementation after bariatric surgery (Roux-en-Y gastric bypass, RYGB) improved muscle strength without significant effect on weight loss and body composition changes. We performed a 5-year follow-up study in these subjects with the aim 1) to assess the long-term effect of this exercise training intervention and 2) to analyze associations between habitual physical activity (PA) and weight regain at 5 years.

Methods: Fifty-four out of 76 initial participants (follow-up rate of 71%) completed the 5-year follow-up examination (controls, n = 17; protein supplementation, n = 22; protein supplementation and resistance training, n = 15). We measured body weight and composition (DXA), lower-limb strength (leg-press one-repetition maximum) and habitual PA (Actigraph accelerometers and self-report). Weight regain at 5 years was considered low when <10% of 12-month weight loss.

Results: Mean (SD) time elapse since RYGB was 5.7 (0.9) y. At 5 years, weight loss was 32.8 (10.1) kg, with a mean weight regain of 5.4 (SD 5.9) kg compared with the 12-month assessment. Moderate-to-vigorous PA (MVPA) assessed by accelerometry did not change significantly compared with pre-surgery values (+5.2 [SD 21.7] min/d, P = 0.059), and only 4 (8.2%) patients reported participation in resistance training. Muscle strength decreased over time (overall mean [SD]: -49.9 [53.5] kg, respectively, P<0.001), with no statistically significant difference between exercise training intervention groups. An interquartile increase in MVPA levels was positively associated with lower weight regain (OR [95% CI]: 3.27 [1.41;9.86]).

Conclusions: Early postoperative participation in a resistance training protocol after bariatric surgery was not associated with improved muscle strength after 5 years of follow-up; however, increasing physical activity of at least moderate intensity may promote weight maintenance after surgery. PA may therefore play an important role in the long-term management of patients with obesity after undergoing bariatric procedure.

Fig 1. Flow chart of the follow-up study.

Fig 2. Associations between weight regain 5 years after RYGB and changes in PA outcomes.

Data are medians (25^th and 75^th percentiles). ^a Non-adjusted P-value from Wilcoxon rank sum test. ^b Logistic regression with accelerometer wear time and baseline preoperative data as covariables (only for accelerometry data). Odds-ratios represent the association between an interquartile range (IQR) increase in PA levels and weight regain (<10% vs. ≥10%). Error bars represent the 95% confidence interval of the OR. Bold values indicate significance with P < 0.05. Self-reported total MVPA is calculated as the sum of leisure-time MVPA and transport-related walking and cycling. Abbreviations: MVPA, moderate-to-vigorous PA.

Fig 3. Type and duration of leisure-time activities performed 5 years after RYGB.

Jogging, indoor aerobic exercise, climbing were reported by one or two patients and are therefore not presented in this figure.