Protein Blends (Soy, Whey and Casein) for Muscle Synthesis

A Randomized, Controlled Double Blind Acute Study: Effects of Protein Blends on Muscle Protein Synthesis and Breakdown

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT01358305

Enrollment

Registered

2011-05-23

Start date

2011-01-31

Completion date

2013-03-31

Last updated

2019-10-07

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Muscle Synthesis

Keywords

muscle, synthesis, mTOR, antioxidant, inflammatory markers, soy protein, whey, casein

Brief summary

Soy protein is a high quality, plant-based protein that is comparable to milk, meat and eggs. Soy protein has a digestion rate (intermediate) compared to whey (fast) and casein (slow). This intermediate rate may allow soy protein to have an extended window of muscle protein synthesis that has not been monitored in previous studies. While most of the sports nutrition recovery products are dairy-based protein blends (high in branched-chain amino acids), soy protein offers additional benefits that can make an important contribution to these types of sports nutrition products. Soy protein contains approximately 300% more arginine and 30% more glutamine compared to whey protein and these two amino acids may bring additional benefits (immunity and hydration, respectively) to athletes. A blend of high-quality proteins (soy and dairy) may be the optimal sports nutrition product for athletes to consume following training.

Interventions

OTHERProtein Blend

Single intake of approximately 20 grams of total protein

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

BASIC_SCIENCE

Masking

TRIPLE (Subject, Caregiver, Investigator)

Eligibility

Sex/Gender

ALL

Age

18 Years to 35 Years

Healthy volunteers

Yes

Inclusion criteria

Inclusion: 1. Age 18-35 yrs 2. Stable body weight for at least 1 year

Exclusion criteria

will be: 1. Exercise training (\>2 weekly sessions of moderate to high intensity aerobic or resistance exercise) 2. Significant heart, liver, kidney, blood, or respiratory disease 3. Peripheral vascular disease 4. Diabetes mellitus or other untreated endocrine disease 5. Active cancer (all groups) and history of cancer (groups potentially randomizable to rapamycin) 6. Acute infectious disease or history of chronic infections (e.g. TB, hepatitis, HIV, herpes) 7. Recent (within 6 months) treatment with anabolic steroids, or corticosteroids. 8. Alcohol or drug abuse 9. Tobacco use (smoking or chewing) 10. Malnutrition (BMI \< 20 kg/m2, hypoalbuminemia, and/or hypotransferrinemia) 11. Obesity (BMI \> 30 kg/m2) 12. Low hemoglobin levels (below normal values) 13. Food allergies 14. Taking dietary supplements such as green tea, etc. 15. Currently on a high-soy diet (consuming \>2 servings of soy per day)

Design outcomes

Primary

Measure	Time frame	Description
Muscle Protein Synthesis or Fractional synthesis rate (FSR)	baseline, 3 hours, 5 hours	The fractional synthesis rate (FSR) of mixed muscle proteins will be calculated from the incorporation rate of L-\[ring-13C6\]Phenylalanine into the mixed muscle proteins, and the free-tissue phenylalanine enrichment.

Secondary

Measure	Time frame	Description
oxidative and inflammatory markers	baseline, 3 hours, 5 hours	Proteins will be assessed that are markers of oxidative damage and inflammation (NFkB, IL-1, IL-6) and proteolysis (MuRF, MAFBx).
Phosphorylation of protein in muscle protein signaling pathways	baseline, 3 hours, 5 hours	Phosphorylation of mTOR, 4E-BP1, S6K1, S6, and eEF2 will be measured using Western blot techniques as previously described.

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026