Oral 'Breath Test' to Measure Anabolic Sensitivity to a Protein Meal Across the Age and Physical Activity Spectrum (NFRF)

Anabolic Sensitivity Across the Lifespan

The purpose of this study is to determine how anabolic sensitivity, in response to the ingestion of a liquid protein meal, differs across the lifespan, between biological sexes, and with varying physical activity levels.

Study Overview

• Status: Not yet recruiting
• Conditions: Physical Activity; Aging; Healthy Aging; Growth & Development; Sex Differences; Protein Metabolism; Inactivity, Physical; Anabolic Sensitivity

Detailed Description

Skeletal muscle is a dynamic tissue that responds to anabolic (i.e., growth) stimuli such as protein ingestion and exercise. Differences in age and physical activity levels will influence an individual's ability to respond to these anabolic stimuli; this concept is known as anabolic sensitivity. For instance, older and less physically active individuals will display lower anabolic sensitivity (i.e., anabolic resistance) to a bout of exercise or the consumption of protein in comparison to younger, more physically active individuals. Seeing that individuals with anabolic resistance are at a greater risk for losing muscle mass over time, it is important to understand the anabolic sensitivity/resistance of an individual to assess for the efficiency of growth across the health and lifespan, in addition to a potential screen for metabolic alterations that could manifest into changes in lean body and muscle mass.

Traditional methods to assess for skeletal muscle anabolism and protein metabolism requires in-person and invasive research methods (i.e., stable isotope infusions and muscle biopsies) in controlled laboratory or clinical settings. However, there are many risks associated with these invasive procedures and they are not always feasible in all populations (e.g., children, clinical populations, etc..). Our lab has recently developed a non-invasive 13C breath test which employs an oral stable isotope tracer. Our breath test allows us to assess for anabolic sensitivity in response to protein ingestion, by determining how much of the ingested protein was used to build (synthesize) new proteins in our body (i.e., anabolism) or used as a source of energy (through a process called oxidation). As such, the purpose of the present study is to determine how anabolic sensitivity, in response to the ingestion of a liquid protein meal, differs across the lifespan and with varying physical activity levels.

• Study Type: Observational
• Enrollment (Estimated): 80

Contacts and Locations

• Study Contact: Name: Daniel R Moore, PhD; Phone Number: 4169464088; Email: dr.moore@utoronto.ca
• Study Contact Backup: Name: Hugo JW Fung, PhD Candidate; Email: hugojernwai.fung@utoronto.ca

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5S 2C9
      • Goldring Center for High Performance Sport
      • Contact: Hugo JW Fung, PhD Candidate; Phone Number: 416-946-5620; Email: hugojernwai.fung@utoronto.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Convenience sample of individuals who qualify for the corresponding cohorts based on inclusion/exclusion criteria stated.

Description

Inclusion Criteria:

• Healthy will be defined as screened by the PAR-Q+ (The Physical Activity Readiness Questionnaire for everyone)
• Chronological age for Healthy Young (age: 18-35 years) or Older (age: 60-80 years) adults
• Chronological age between 8 to 16 years, with maturity offset < -1 year from age of Peak Height Velocity (aPHV) for children and between -0.5 to +1.5 years from aPHV in adolescent participants
• BMI between normal to overweight (18.5 - 29.9 kg/m2)

Exclusion Criteria:

• Regular use of nonsteroidal anti-inflammatory dugs (with the exception of daily low-dose aspirin)
• use of anticoagulants
• use of a walker, cane, or assistive walking device
• infectious or gastrointestinal disease
• inability to comply with study protocol (e.g., unable to track diet)
• regular tobacco use
• self-reported illicit drug use (e.g., growth hormone, testosterone, etc.)
• diagnosed chronic illness (e.g., type 2 diabetes, heart disease, thyroid disease)
• pregnant
• hormonal replacement therapy

Study Plan

How is the study designed?

Number of groups / cohorts

4

Cohorts and Interventions

Group / Cohort
Children; Children as defined by maturity offset via age from peak height velocity (aPHV < -1.0 years).
Adolescent; Adolescents as defined by maturity offset via age from peak height velocity (aPHV -0.5 to +1.5 years)
Young Adults; Young adults as defined by chronological age between ages 18 - 35 years
Older Adults; Older adults as defined by chronological age between ages 60 - 80 years

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Amino acid oxidation and net protein balance	Amino acid oxidation and net protein balance assessed by oral 1-13C Leucine tracer. Net protein balance is derived from the difference between amino acid intake (known) and total amino acid oxidation over the 6h post-prandial measurement period.	6 Hours

Collaborators and Investigators

• Sponsor: University of Toronto

Study record dates

Study Major Dates

• Study Start (Estimated): December 20, 2024
• Primary Completion (Estimated): May 30, 2025
• Study Completion (Estimated): August 31, 2025

Study Registration Dates

• First Submitted: December 16, 2024
• First Submitted That Met QC Criteria: December 16, 2024
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: December 16, 2024
• Last Verified: November 1, 2024

More Information

Terms related to this study

• Keywords: physical activity; aging; skeletal muscle; growth and development; stable isotopes; anabolic sensitivity
• Additional Relevant MeSH Terms: Immune System Diseases; Hypersensitivity
• Other Study ID Numbers: 00044004

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No