Table 1. Characteristics of included studies.

Study	Country	Study design	Aim of the study	Sample	Type of bariatric surgery	Postoperative time
Stegen et al., 2011	Belgium	NRCT	To investigate the effect of RYGB on physical fitness and to determine if an exercise program in the first 4 months is beneficial.	15 ♀♂ Age: 40.5 ± 8.1 BMI > 35	RYGB	1 month
Huck, 2015	USA	NRCT	To evaluate the feasibility of a 12-week supervised, resistance training program and its short-term effects on physical fitness and functional strength for this population	15 ♀♂ Age: 18–65 BMI: 37.7 ± 6.3	RYGB/GB	≤ 12 months
Campanha-Versiani et al., 2017	Brazil	NRCT	To evaluate bone mineral density and bone markers in a group submitted to a regular and supervised exercise program compared to a control group that did not perform exercises and evaluate muscular strength and body composition after 1 year of a combined program of weight-bearing and aerobic exercise, in obese patients who have undergone RYGB.	37 ♀♂ Age: 20–60 BMI > 40	RYGB	2 months
Coleman et al., 2017	USA	RCT	To conduct a pilot randomized trial testing an exercise program specifically adapted for post-bariatric patients.	44♀♂ Age: 49.8 ± 11.4 BMI: 30–35	RYGB/Sleeve/GB	6–24 months
Hassannejad et al., 2017	Iran	RCT	To evaluate the impact of aerobic and strength exercise after the bariatric surgery on weight loss and body composition outcomes and to investigate the improvement in functional capacity.	60 ♀♂ Age: 20–50 BMI > 35	RYGB/Sleeve	1 month
Herring et al., 2017	UK	RCT	To examine the effects of a supervised 12-week exercise intervention on physical function and body composition maintenance in patients who were between 12 and 24 months after bariatric surgery.	24 ♀♂ Age: >18 BMI > 30	RYGB/Sleeve/GB	12–24 months
Daniels et al., 2018	USA	RCT	To examine the effect of a 12-week resistance training programme on lean mass, muscle cross-sectional area, muscular strength and muscle quality in women who underwent RYGB surgery.	16 ♀ Age: 44.9±10.2 BMI NA	RYGB	2 months
Mundbjerg et al., 2018	Denmark	RCT	To investigate the effects of supervised physical training following RYGB on aerobic capacity, muscle strength and physical function 12–24 months post-surgery and furthermore to elucidate the effects of RYGB from pre-surgery to 6 months post-surgery on the same markers for physical capacity.	52 ♀ ♂ Age: 42.3±9.1 BMI 33.7±5.8	RYGB	6 months
Kelley, 2019	USA	RCT	To investigate the effects of eccentric exercise on lower body skeletal muscle mass during rapid body mass loss induced by bariatric surgery	13 ♀ Age: 37.9±8.1 BMI 39.3±4.3	RYGB/Sleeve	1–2 months
Noack-Segovia et al., 2019	Chile	RCT	To evaluate a physical exercise program of moderate intensity in patients operated of bariatric surgery and its influence on muscle strength.	43 ♀ ♂ Age: 33.0±6.9 BMI 35.5±3.3	NA	1 month
Gallé et al., 2020	Italy	NRCT	To evaluate the effects of an integrated post-operative exercise-based educational and motivational program implemented immediately after surgery on lifestyles, quality of life, anthropometry, cardiorespiratory fitness, muscular strength and flexibility respect to the only surgical intervention in a sample of Italian sedentary bariatric patients.	70 ♀ ♂ Age: 18–65 BMI 33.8±5.1	Sleeve/GB	≤ 6 months
de Oliveira Junior et al., 2021	Brazil	RCT	To investigate the impact of a home-based exercise training program in patients who had surgery and were provisionally deprived from in-hospital health care.	70 ♀♂ Age: 47.5±11.6 BMI: 36.0±6.8	RYGB/Sleeve	3–12 months
Diniz-Souza et al., 2021	Portugal	RCT	To investigate whether a supervised multicomponent exercise program could induce benefits on bone mass after bariatric surgery.	61 ♀ ♂ Age: 18–65 BMI ≥ 35	RYGB/Sleeve	1 month
Gil et al., 2021	Brazil	RCT	To comprehensively examine the effects of exercise training on body composition (fat-free mass as primary outcome), muscle function and related cellular and molecular mechanisms (secondary outcomes) in women undergoing bariatric surgery.	55 ♀ Age: 18–60 BMI ≥ 35	RYGB	3 months
Lamarca et al., 2021	Brazil	NRCT	To investigate the effects of resistance training with and without whey protein supplementation on body composition and Resting Energy Expenditure in the late postoperative period of RYGB.	63 ♀ ♂ Age: 40.3±8.3 BMI 29.7±5.3	RYGB	24–84 months

Age, years; BMI, Body mass index (Kg/m²); GB, Gastric banding; NA, Not available; Max, Maximum; NRCT, Non-randomized controlled trial; RCT, Randomized controlled trial; RYGB, Roux-en-Y gastric bypass; Sleeve, Sleeve gastrectomy; UK, United Kingdom; USA, United States of America. ♀ for female and ♂ for male.