Muscle Hypertrophy, Bone Mineral Density Loss, Resistance Training Adaptation
Conditions
Keywords
Whey Protein, Collagen Peptides, Resistance Training, Muscle Mass, Bone Mineral Density, Bone Turnover Biomarkers, Strength Training, Protein Supplementation, Hypertrophy, Sports Nutrition
Brief summary
This study tested whether taking whey protein together with collagen peptides would provide greater benefits for muscle and bone health compared to whey protein alone, collagen alone, or a placebo. Forty healthy, resistance-trained men aged 18-35 years were randomly assigned to one of four groups: (1) whey protein plus collagen (30 g + 10 g/day), (2) whey protein only (30 g/day), (3) collagen only (10 g/day), or (4) placebo (maltodextrin). All participants followed a supervised resistance training program (3 times per week) for 8 weeks. The primary outcome was muscle mass, measured with bioelectrical impedance analysis (BIA). Secondary outcomes included bone mineral density (DXA scans), maximal strength (1RM squat and bench press), and blood markers of bone turnover (P1NP and CTX-I). Results showed that the whey + collagen group achieved the largest improvements in muscle growth, lumbar spine bone mineral density, strength, and favorable changes in bone turnover markers compared to all other groups. No serious side effects were reported, and supplement adherence was very high. These findings suggest that combining whey protein and collagen may be a practical strategy to support muscle and bone adaptation in resistance-trained men.
Detailed description
This was a double-blind, randomized, placebo-controlled trial evaluating the combined effects of whey protein and collagen supplementation on muscle mass, bone mineral density (BMD), muscular strength, and bone turnover markers in resistance-trained men. Forty healthy male participants (18-35 years, with ≥1 year of resistance training experience) were recruited and randomized into four parallel groups (n=10 per group): Whey Protein + Collagen (30 g WP + 10 g collagen/day) Whey Protein only (30 g/day) Collagen only (10 g/day) Placebo (10 g maltodextrin/day, isocaloric) All supplements were provided in identical single-dose sachets to ensure blinding. Participants consumed one dose upon waking and one post-exercise (or same time on rest days). A standardized, supervised hypertrophy-oriented resistance training program (3 sessions/week for 8 weeks) was applied to all groups. Primary outcome: Muscle mass (lean body mass, assessed with BIA at baseline and 8 weeks). Secondary outcomes: Lumbar spine and femoral neck BMD (DXA), maximal squat and bench press strength (1RM), and serum biomarkers of bone turnover (P1NP and CTX-I). The trial was approved by the Islamic Azad University IRB (Protocol No: IAU.Ilk.C.162911421.2024). All participants gave written informed consent. Compliance with supplementation was \>90% and training adherence was \>95%. No adverse events were reported.
Interventions
DIETARY_SUPPLEMENTWhey Protein + Collagen
Participants consumed 30 g/day whey protein isolate (Optimum Nutrition) combined with 10 g/day type I & III collagen peptides (Vital Proteins). Supplements were provided as single-dose sachets, identical in appearance, and taken twice daily (morning and post-exercise or same time on rest days) for 8 weeks.
DIETARY_SUPPLEMENTWhey Protein
Participants consumed 30 g/day whey protein isolate (Optimum Nutrition), in identical sachets, taken twice daily for 8 weeks.
DIETARY_SUPPLEMENTCollagen Peptides
Participants consumed 10 g/day type I & III collagen peptides (Vital Proteins), in identical sachets, taken twice daily for 8 weeks.
OTHERMaltodextrin (Placebo)
Participants consumed 10 g/day maltodextrin powder (isocaloric to protein supplements), packaged identically, taken twice daily for 8 weeks.
Sponsors
Saglik Bilimleri Universitesi
Islamic Azad University of Mashhad
Manisa Celal Bayar University
Muş Alparslan University
Pamukkale University
Australian Catholic University
Ankara Yildirim Beyazıt University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Masking description
Double-blind design extended to all relevant parties. Supplements were provided in identical, opaque sachets to ensure concealment. Randomization sequence was managed by an independent statistician not involved in data collection or analysis. Participants, trainers, investigators, and outcome assessors remained blinded to group assignments until completion of analyses.
Intervention model description
Participants were randomly assigned into one of four parallel groups (Whey + Collagen, Whey only, Collagen only, Placebo). Each group received its allocated supplementation daily for 8 weeks in combination with a standardized resistance training program. Groups were followed concurrently with no crossover.
Eligibility
Sex/Gender
MALE
Age
18 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
* Male participants aged 18-35 years * At least 1 year of consistent resistance training experience (≥3 sessions per week, targeting major muscle groups) * Healthy, with no history of musculoskeletal, metabolic, or cardiovascular disorders * No current or recent (\<6 months) use of anabolic steroids, growth hormones, or performance-enhancing substances * Non-smoker and no habitual use of anti-inflammatory medications * Able and willing to comply with supplementation and supervised training program * Provided written informed consent
Exclusion criteria
* Participation in similar supplementation studies in the past 6 months * Recent fractures or surgeries affecting musculoskeletal health (\<6 months) * Known allergy or intolerance to dairy proteins or collagen supplements * Inability to attend scheduled supervised resistance training sessions * Non-adherence to dietary control requirements (e.g., use of additional protein/creatine supplements during study) * Any condition deemed by investigators to interfere with study compliance or safety
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Muscle Mass (kg, lean body mass by BIA) | Baseline (week 0) to 8 weeks post-intervention | Muscle mass was assessed using bioelectrical impedance analysis (InBody 770). Measurements were conducted under standardized conditions (≥8 h fasted, no exercise or caffeine for ≥12 h, urine specific gravity \<1.020). Values reported as lean body mass (kg). Primary analysis compared changes between Whey + Collagen, Whey only, Collagen only, and Placebo groups after 8 weeks of supplementation combined with resistance training. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Lumbar Spine Bone Mineral Density (BMD) | Baseline to 8 weeks | BMD measured at lumbar spine (L1-L4) using DXA (Hologic Discovery A). Scans performed by trained technician with daily calibration. |
| Change in Femoral Neck Bone Mineral Density (BMD) | Baseline to 8 weeks | BMD measured at femoral neck using DXA, reported in g/cm². |
| Change in Squat Strength (1RM) | Baseline to 8 weeks | Maximal squat strength (kg) assessed via 1-repetition maximum (1RM) testing under standardized protocol, supervised by certified trainers. |
| Change in Bench Press Strength (1RM) | Baseline to 8 weeks | Maximal bench press strength (kg) assessed via standardized 1RM testing, supervised by certified trainers. |
| Change in Procollagen Type I N-Terminal Propeptide (P1NP) | Baseline to 8 weeks | Serum P1NP, a marker of bone formation, measured via ELISA. Blood collected after overnight fast (7:00-9:00 AM), samples stored at -80°C. |
Countries
Turkey (Türkiye)
Outcome results
None listed