Protein Requirements Amongst Male Masters-Level Athletes Following a Cycling Exercise Bout as Determined by the Indicator Amino Acid Oxidation Technique

NCT06431334 | Recruiting

• 1 other identifier: A06-M25-23A
• Study Type: interventional
• Target: 8
• Locations: 1 country
• Sites: 1

Brief Summary

Masters level cyclists are a population above the age of 35 years who frequently participate in prolonged as well as heavy-volume training. Like most endurance-trained athletes, a greater recommended dietary allowance (RDA) for protein of 1.2-1.4 g/kg/bw is suggested. Dietary protein intake is vital for maximizing the benefits of training and ensuring optimal recovery. Dietary recommendations traditionally have been determined through nitrogen balance techniques, however, recent research indicates how this method is potentially underestimating protein requirements. Therefore, there is a need to reassess current dietary recommendations in order to meet the demands of physical activity for highly active populations. Recent efforts to understand protein requirements during rest and following exercise have been completed using the indicator amino acid technique (IAAO). This non-invasive method is reported to provide a robust measure of protein requirements. However, there is limited work in older (≥60 years) active populations. The purpose of this study is to measure the protein requirements in master cyclists, following an endurance training session, using the non-invasive IAAO technique.

Conditions

Dietary Reference Intakes; Healthy; Increased Metabolic Requirements

Outcome Measures

Primary Outcomes (1)

• 13CO2 Excretion

  Measured by continuous-flow isotope ratio mass spectrometry

  7-weeks

Secondary Outcomes (1)

• L[13C]phenylalanine Oxidation

  7-weeks

Study Arms (1)

Masters Level Cyclists

EXPERIMENTAL

Participants are to be randomly assigned varying levels of amino acid intakes ranging between 0.2 to 2.8 g/kg/d

Dietary Supplement: Amino Acid Intake

Interventions

Amino Acid Intake DIETARY_SUPPLEMENT

Amino acid intakes will vary between 0.2 to 2.8 g/kg/d

Masters Level Cyclists

Eligibility Criteria

• Age: 65 Years+
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Older Adult (65+)

You may qualify if:

• \< BMI \<35 kg/m\^2
• Overtly healthy masters level cyclists ≥65 years
• Masters level cyclist training (\>4 days per week; \~100 km per week)
• Body mass stable over previous 6-months
• Availability for multiple metabolic trials (\~7 trials)
• Ability to travel to and from laboratory facility

You may not qualify if:

• Recent history of weight loss or weight gain (\>5% body weight)
• Uncontrolled hypertension
• ≥2 chronic diseases (e.g. diabetes, osteoporosis, dyslipidemia)
• Acute illness that could affect protein metabolism (HIV, renal dysfunction, influenza)
• Currently using anti-inflammatory medications
• Inability to adhere to study protocol (i.e., alcohol, caffeine, dietary restrictions)
• Regular tobacco user
• Illicit drug use
• Habitually ingesting ≥3 g/kg/bw

Sponsors & Collaborators

• McGill University: lead

Study Sites (1)

McGill University

Montreal, Quebec, H3A 0G4, Canada

RECRUITING

Central Study Contacts

Tyler A. Churchward-Venne, Ph.D.

CONTACT

(514) 398-4184; tyler.churchward-venne@mcgill.ca

Damian Papadopoulos, B.Sc

CONTACT

(514) 561-7860; damian.papadopoulos@mail.mcgill.ca

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: May 22, 2024
• First Posted: May 28, 2024
• Study Start: June 21, 2024
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): June 1, 2026
• Last Updated: February 9, 2026

Record last verified: 2026-02

Locations

CA (1)