Preventing Muscle Loss After Bariatric Surgery: Protein-Collagen Supplementation and Resistance Exercise

NCT07303543 | Recruiting

• 1 other identifier: E-66291034-772.02-3053
• Study Type: interventional
• Target: 35
• Locations: 1 country
• Sites: 1

Brief Summary

The aim of this clinical trial is to investigate the effectiveness of collagen, considered a new approach to prevent muscle mass loss after bariatric surgery, and to demonstrate the relationship between this effect and exercise. The key questions it aims to answer are: Does whey protein supplementation with collagen combined with resistance exercise prevent muscle mass loss after bariatric surgery? Do whey protein supplementation with collagen combined with resistance exercise affect fat mass after bariatric surgery? Researchers will compare collagen with whey protein. The study groups and interventions to be implemented are summarized below: Group 1: Control Group (CG; n: 10) Whey protein supplementation will be administered Vitamin and mineral supplementation will be administered No resistance exercise will be performed The participants will eat according to bariatric surgery nutrition guidelines and perform physical activities. Group 2: Whey Protein + Collagen + Exercise Group (WPCEG; n: 10) Whey protein supplements with collagen will be given. Vitamin and mineral supplements will be given. Resistance exercise will be performed. They will eat according to bariatric surgery nutrition guidelines and perform physical activities. They will begin a resistance exercise program 4 weeks after surgery. Group 3: Whey Protein + Collagen + No Exercise Group (WPCG; n: 10) Whey protein supplements with collagen will be given. Vitamin and mineral supplements will be given. No resistance exercise will be performed. They will eat according to bariatric surgery nutrition guidelines and perform physical activities. Group 4: Whey Protein + Exercise Group (WPEG; n: 10) Whey protein supplements will be given. Vitamin and mineral supplements will be given. Resistance exercise will be performed. They will eat according to bariatric surgery nutrition guidelines and perform physical activities. A resistance exercise program will begin at 4 weeks post-operatively.

Conditions

Bariatric Surgery; Muscle Loss

Keywords

Bariatric Surgery; Collagen; Resistance exercise; Whey protein; Muscle loss

Outcome Measures

Primary Outcomes (1)

• Change in Skeletal Muscle Mass (kg) Measured by BIA

  Skeletal muscle mass (kg) will be measured using a multi-frequency bioelectrical impedance analysis (BIA) device. The outcome will be reported as the mean change from baseline at each time point in each study group.

  Baseline (preoperative), postoperative week 4 (day 29), and postoperative week 12 (day 85)

Secondary Outcomes (1)

• Change in Fat Mass (kg) Measured by BIA

  Baseline, week 4, and week 12

Study Arms (4)

Control Group (CG)

ACTIVE COMPARATOR

Whey protein supplementation will be provided. Vitamin and mineral supplementation will be administered. No resistance exercise will be performed. Participants will follow bariatric surgery nutrition guidelines and maintain their regular physical activities. A comparison will be made with the other groups as the control group.

Dietary Supplement: Whey protein supplement; Dietary Supplement: Vitamin and Mineral Supplementation

Whey Protein + Collagen + Exercise Group (WPCEG)

EXPERIMENTAL

Collagen-containing whey protein supplementation will be provided. Vitamin and mineral supplementation will be given. Resistance exercises will be performed. Participants will follow bariatric surgery nutrition guidelines and maintain their physical activities. They will begin the resistance exercise program in the 4th week after surgery.

Dietary Supplement: Whey protein supplement; Dietary Supplement: Hydrolyzed Collagen Supplement; Dietary Supplement: Vitamin and Mineral Supplementation; Behavioral: Resistance Exercise Program

Whey Protein + Collagen + Non-Exercise Group (WPCG)

EXPERIMENTAL

Collagen-containing whey protein supplementation will be provided. Vitamin and mineral supplementation will be administered. No resistance exercises will be performed. Participants will follow bariatric surgery nutrition guidelines and maintain their physical activities.

Dietary Supplement: Whey protein supplement; Dietary Supplement: Vitamin and Mineral Supplementation

Whey Protein + Exercise Group (WPEG)

EXPERIMENTAL

Whey protein supplementation will be provided. Vitamin and mineral supplementation will be given. Resistance exercises will be performed. Participants will follow bariatric surgery nutrition guidelines and maintain their physical activities. They will begin the resistance exercise program in the 4th week after surgery.

Dietary Supplement: Whey protein supplement; Dietary Supplement: Vitamin and Mineral Supplementation; Behavioral: Resistance Exercise Program

Interventions

Whey protein supplement DIETARY_SUPPLEMENT

Oral whey protein supplement provided daily according to bariatric surgery nutrition protocol.

Control Group (CG); Whey Protein + Collagen + Exercise Group (WPCEG); Whey Protein + Collagen + Non-Exercise Group (WPCG); Whey Protein + Exercise Group (WPEG)

Hydrolyzed Collagen Supplement DIETARY_SUPPLEMENT

Oral hydrolyzed collagen supplement provided daily in combination with whey protein.

Whey Protein + Collagen + Exercise Group (WPCEG)

Vitamin and Mineral Supplementation DIETARY_SUPPLEMENT

Routine vitamin and mineral supplementation according to bariatric surgery follow-up protocol.

Control Group (CG); Whey Protein + Collagen + Exercise Group (WPCEG); Whey Protein + Collagen + Non-Exercise Group (WPCG); Whey Protein + Exercise Group (WPEG)

Resistance Exercise Program BEHAVIORAL

Structured resistance exercise program initiated at postoperative week 4, supervised, 3 times per week.

Whey Protein + Collagen + Exercise Group (WPCEG); Whey Protein + Exercise Group (WPEG)

Eligibility Criteria

• Age: 20 Years - 50 Years
• Gender Eligibility Details: man and woman
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Being between 20-50 years old
• Body mass index; 35 ≤ BMI\< 60 kg/m2
• Not being pregnant
• Not being addicted to alcohol and drugs
• Not having entered menopause
• No exercise restrictions

You may not qualify if:

• Having at least one of the following inflammatory bowel diseases, upper gastrointestinal bleeding, advanced psychiatric diseases, cancer, and kidney failure.
• using statins
• be pregnant
• Being addicted to alcohol and drugs
• to have entered menopause
• Having exercise restrictions
• Becoming a professional athlete
• Having done more than 60 minutes of regular and structured exercise per week in the last year

Sponsors & Collaborators

• Medipol University: lead

Study Sites (1)

Istanbul Medipol University

Istanbul, Fatih, Turkey (Türkiye)

RECRUITING

MeSH Terms

Conditions

Muscular Atrophy

Interventions

Vitamins

Condition Hierarchy (Ancestors)

Neuromuscular Manifestations; Neurologic Manifestations; Nervous System Diseases; Atrophy; Pathological Conditions, Anatomical; Pathological Conditions, Signs and Symptoms; Signs and Symptoms

Intervention Hierarchy (Ancestors)

Micronutrients; Physiological Effects of Drugs; Pharmacologic Actions; Chemical Actions and Uses; Nutrients; Food; Diet, Food, and Nutrition; Physiological Phenomena; Food and Beverages

Study Officials

• Halit E Taşkın, Dr.

  Cerrahpaşa Faculty of Medicine, General Surgery

  PRINCIPAL INVESTIGATOR

• Nihal Z Erdem, PhD

  Istanbul Medipol University, Nutrition and Dietetics

  PRINCIPAL INVESTIGATOR

• Bürke Köksalan, PhD

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Rüken A Samancı, Msc

CONTACT

+90 543 939 15 94; rasamanci@medipol.edu.tr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Lecturer

Study Record Dates

• First Submitted: November 17, 2025
• First Posted: December 26, 2025
• Study Start: August 2, 2022
• Primary Completion: December 20, 2025
• Study Completion: January 30, 2026
• Last Updated: December 26, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)