Protein Quality to Support Increased Muscle Protein Synthesis

Efficacy of Higher Versus Lower Quality Protein Supplementation to Support Increased Muscle Protein Synthesis in Older Men

The age-related decline in muscle mass and strength is collectively referred to as sarcopenia. Canadian recommended daily allowance (RDA) for protein intake (0.8 g/kg/d), however, many expert groups have advocated that older persons should increase their daily intake to ~1.2 g/kg/d to support the preservation of muscle mass. The use of plant-based proteins in food formulation has recently become of interest. This study will examine the impact of consuming higher- versus lower-quality protein supplements on muscle protein synthesis in healthy older men.

This study will examine the impact of consuming higher- versus lower-quality protein supplements on the integrated rates of muscle protein synthesis in healthy older men. Briefly, participants will consume dietary protein at the RDA for the entire duration of the protocol (2 weeks). Participants will be randomized to consuming collagen (control - CON), whey (WHEY), or pea (PEA) protein supplements twice daily for one week. We will examine the ability of different qualities of protein supplements to stimulate integrated rates of muscle protein synthesis.

Inclusion Criteria:

1. Men, between the ages of 65 - 80 years (inclusive)
2. Willing and able to provide informed consent
3. Be in general good health, non-smoking
4. Have a body mass index (BMI) between 20-38 kg/m2 (inclusive)

Exclusion Criteria:

1. Use of tobacco or related products.
2. Veganism or vegetarianism
3. Any concurrent medical, orthopedic, or psychiatric condition that, in the opinion of the Investigator, would compromise his/her ability to comply with the study requirements.
4. Use assistive walking devices (e.g., cane or walker)
5. History of cancer within the last 5 years, except basal cell carcinoma, non-squamous skin carcinoma, prostate cancer or carcinoma in situ with no significant progression over the past 2 years.
6. Significant orthopedic, cardiovascular, pulmonary, renal, liver, infectious disease, immune disorder, or metabolic/endocrine disorders or other disease that would preclude oral protein supplement ingestion and/or assessment of safety and study objectives.
7. Any cachexia-related condition (e.g., relating to cancer, tuberculosis or human immunodeficiency virus infection and acquired immune deficiency syndrome) or any genetic muscle diseases or disorders
8. Current illnesses which could interfere with the study (e.g. prolonged severe diarrhea, regurgitation, difficulty swallowing)
9. Hypersensitivity or known allergy to any of the components in the test formulations.
10. Excessive alcohol consumption (>21 units/week)
11. History of bleeding diathesis, platelet or coagulation disorders, or antiplatelet/anticoagulation therapy (up to 81mg of baby aspirin per day taken as a prophylactic is permitted).
12. History of statin myalgia.
13. Personal or family history of clotting disorder or deep vein thrombosis;
14. Routine/daily usage of non-steroidal anti-inflammatory drugs (NSAIDS, prescription use or daily use of over the counter medication), use of corticosteroids, testosterone replacement therapy (ingestion, injection, or transdermal), any anabolic steroid, creatine, whey protein supplements, casein or branched-chain amino acids (BCAAs) within 45 days prior to screening.