NCT04981652

Brief Summary

Muscle and strength begin to noticeably decline around 50 years of age, increasing an individual's risk for disease and disability. Although changes in muscle mass ultimately depend on the balance of muscle protein synthesis (MPS) and breakdown (MPB) of muscle proteins, the latter remains relatively constant with aging. Accordingly, interventions that increase rates of MPS may combat long-term decrements in skeletal muscle mass and function. Previous research has established that an optimal diet to maintain muscle mass in elderly individuals requires relatively large amounts of high-quality protein to be consumed at each meal of the day. While this is a seemingly simple strategy, there are some barriers to increasing protein feeding in elderly individuals, particularly the cost of high-quality protein and, sometimes, difficulty with chewing/swallowing. Moreover, older adults often do not wish to consume large portions of protein in one meal. Milk is a readily accessible, affordable and nutritious source of nutrient-dense high-quality protein. Consuming milk with each meal is an easy strategy to promote the maintenance of skeletal muscle mass with aging. There is also evidence suggesting that a higher fat content of milk can have a beneficial role in stimulating the MPS response to feeding, but there are insufficient data to recommend this strategy to elderly individuals. The primary aim is to measure the rates of MPS in response to controlled diets providing whole milk, fat-free milk, or a control supplement (almond beverage - often marketed as an 'alternative' to milk) with each meal. All diets will provide equal amounts of energy, but the dairy interventions will provide more protein, reflecting the amount of protein provided by each beverage. The investigators hypothesize that rates of MPS will be highest in the whole milk group but that fat-free milk will still elicit a greater MPS than almond beverage. The investigators will conduct the comparison of beverages under habitual physical activity levels and under a brief period of increased physical activity (i.e., increased daily steps). Thus, the investigators will be able to determine whether MPS responses to the experimental beverages are increased in combination with physical activity. The results will provide evidence regarding the effectiveness of daily milk ingestion for the maintenance of muscle in the elderly, increasing the marketability of milk, and potentially whole milk.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
24

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Jun 2018

Typical duration for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Start

First participant enrolled

June 1, 2018

Completed
1.8 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 1, 2020

Completed
6 months until next milestone

Study Completion

Last participant's last visit for all outcomes

September 1, 2020

Completed
11 months until next milestone

First Submitted

Initial submission to the registry

July 19, 2021

Completed
10 days until next milestone

First Posted

Study publicly available on registry

July 29, 2021

Completed
Last Updated

April 6, 2022

Status Verified

April 1, 2022

Enrollment Period

1.8 years

First QC Date

July 19, 2021

Last Update Submit

April 4, 2022

Conditions

Outcome Measures

Primary Outcomes (1)

  • Muscle Protein Synthesis

    Muscle protein synthesis will be calculated by determining the change in deuterated alanine enrichment in skeletal muscle proteins over each study phase

    Assessed at baseline (day 0-3), intervention diet (4-7) and intervention diet + activity (day 8-10)

Secondary Outcomes (1)

  • Western Blotting

    Assessed at baseline (day 0-3), intervention diet (4-7) and intervention diet + activity (day 8-10)

Study Arms (3)

Whole Milk

EXPERIMENTAL

Participants randomly assigned to the whole milk condition will undergo three sequential study phases, each lasting three days in length. During phase 1, these participants will participate in habitual physical activity and consume a standardized diet, delivering 0.8 g/kg/body mass per day of protein. During the second phase, participants in this group will continue to perform habitual activity, but will have two whole milk experimental beverages (250 mL each serving, 3% milk fat) added to their standardized diet each day for the three day period. Finally, during the last three days of the study, participants will continue to consume the their intervention diet, but their physical activity levels (monitored via daily step count) will be increased to \~150% of their habitual levels.

Dietary Supplement: Whole Milk

Skim Milk

EXPERIMENTAL

Participants randomly assigned to the skim milk condition will undergo three sequential study phases, each lasting three days in length. During phase 1, these participants will participate in habitual physical activity and consume a standardized diet, delivering 0.8 g/kg/body mass per day of protein. During the second phase, participants in this group will continue to perform habitual activity, but will have two skim milk experimental beverages (250 mL each serving, 0% milk fat) added to their standardized diet each day for the three day period. Finally, during the last three days of the study, participants will continue to consume the their intervention diet, but their physical activity levels (monitored via daily step count) will be increased to \~150% of their habitual levels.

Dietary Supplement: Skim Milk

Almond Beverage

EXPERIMENTAL

Participants randomly assigned to the almond beverage condition will undergo three sequential study phases, each lasting three days in length. During phase 1, these participants will participate in habitual physical activity and consume a standardized diet, delivering 0.8 g/kg/body mass per day of protein. During the second phase, participants in this group will continue to perform habitual activity, but will have two almond experimental beverages (250 mL each serving) added to their standardized diet each day for the three day period. Finally, during the last three days of the study, participants will continue to consume the their intervention diet, but their physical activity levels (monitored via daily step count) will be increased to \~150% of their habitual levels.

Dietary Supplement: Almond Beverage

Interventions

Whole MilkDIETARY_SUPPLEMENT

Participants will consume twice daily whole milk beverages in addition to a standardized diet.

Whole Milk
Skim MilkDIETARY_SUPPLEMENT

Participants will consume twice daily skim milk beverages in addition to a standardized diet.

Skim Milk
Almond BeverageDIETARY_SUPPLEMENT

Participants will consume twice daily almond beverages in addition to a standardized diet.

Almond Beverage

Eligibility Criteria

Age60 Years - 75 Years
Sexfemale
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Be between the ages of 60-75 years (inclusive)
  • Be at least 5 years post-menopausal
  • Have a body mass index (BMI) between 20-35 kg/m2
  • Be able to maintain a habitual diet, physical activity patterns, and body mass throughout the trial
  • Be in general good health
  • Understand the study procedures and sign this form providing informed consent to participate in the study.
  • Understand the study procedures and sign the form providing informed consent to participate in the study.

You may not qualify if:

  • Use of tobacco or related products
  • Use assistive walking devices (e.g., cane or walker)
  • A history of neuromuscular problems or muscle and/or bone wasting diseases
  • Any acute or chronic illness; cardiac, pulmonary, liver, or kidney abnormalities; insulin- or non-insulin-dependent diabetes or other metabolic disorders (all ascertained through medical questionnaires)
  • Use of medications known to affect protein metabolism (i.e. corticosteroids, nonsteroidal anti-inflammatory drugs (prescription use or daily use of over the counter medication), or prescription strength acne medications)
  • Use of anticoagulant medication
  • History of statin myalgia
  • Allergy to lactose or almonds
  • Consuming a vegan diet

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Exercise Metabolism Research Laboratory, McMaster Univeristy

Hamilton, Ontario, L8S 4K1, Canada

Location

Related Publications (1)

  • Stokes T, Mei Y, Seo F, McKendry J, McGlory C, Phillips SM. Dairy and Dairy Alternative Supplementation Increase Integrated Myofibrillar Protein Synthesis Rates, and Are Further Increased when Combined with Walking in Healthy Older Women. J Nutr. 2022 Jan 11;152(1):68-77. doi: 10.1093/jn/nxab358.

MeSH Terms

Conditions

Motor Activity

Condition Hierarchy (Ancestors)

Behavior

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
PARTICIPANT
Masking Details
Participant was blinded by formulating intervention beverages to have a similar taste profile with noncaloric, non-nutritional flavouring additives
Purpose
BASIC SCIENCE
Intervention Model
PARALLEL
Model Details: Participants randomly assigned to one of three intervention groups (whole milk, skim milk or almond beverage)
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor

Study Record Dates

First Submitted

July 19, 2021

First Posted

July 29, 2021

Study Start

June 1, 2018

Primary Completion

March 1, 2020

Study Completion

September 1, 2020

Last Updated

April 6, 2022

Record last verified: 2022-04

Data Sharing

IPD Sharing
Will not share

Locations