Protein and Performance (PROPER) in Endurance Athletes

NCT05426447 | Active Not Recruiting

• 1 other identifier: PROPER
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

The present study is a parallel group design with randomised allocation to either a 1) reduced protein diet (RP) or a 2) normal protein diet (NP). The two groups will be pair-matched based on habitual dietary protein intake, endurance training, endurance performance, and sex. The aim of the study is to investigate the effects of reducing dietary protein (\~1g protein/kg body mass) compared to an eucaloric normal protein diet (\~2g protein/kg body mass) for 6 weeks in well-trained endurance athletes on endurance performance, body composition, skeletal muscle protein synthesis, and health-related outcomes. The hypothesis is that endurance performance will maintain or even be improved in well-trained endurance athletes after a 6-week dietary intervention of an eucaloric, protein reduced diet compared to a normal protein rich diet.

Conditions

Diet, Healthy; Protein Deficiency

Keywords

Diet intervention; Endurance athletes; Endurance performance; Skeletal muscle protein synthesis; Protein intake; Health markers; Microbiome

Outcome Measures

Primary Outcomes (2)

• Endurance performance on a bike

  Endurance performance defined as maximal aerobic power (Wmax) during incremental test to exhaustion on a bike measured as 1-minute mean power output (W)

  From Pre (week0) to post (week6)

• Microbiome

  Diversity of bacterial strains in gut microbiome measured in feces samples

  Run-in (week-3 to week0) vs dietary intervention (week0 to week6)

Secondary Outcomes (39)

• Resting metabolic rate

  Pre (week0) to mid (week3)

• Resting metabolic rate

  Pre (week0) to Post (week6)

• Lean body mass

  Run-in (week-3) to Pre (week0)

• Lean body mass

  Pre (week0) to Post (week6)

• Total fat mass

  Pre (week0) to Post (week6)

Study Arms (2)

Reduced protein diet

EXPERIMENTAL

A 6-week eucaloric dietary intervention of reduced protein intake (\~1g protein/kg body mass). The diet will, hence, contain \~7E% protein, \~63E% carbohydrate, and \~29E% fat. Participants are free-living and receive all food pre-packed from the study kitchen. The energy provision will be set to match energy balance.

Other: Dietary intervention of reduced protein intake

Normal protein diet

ACTIVE COMPARATOR

A 6-week eucaloric dietary intervention of normal protein intake (\~2g protein/kg body mass). The diet will, hence, contain \~16E% protein, \~53E% carbohydrate, and \~30E% fat. Participants are free-living and receive all food pre-packed from the study kitchen. The energy provision will be set to match energy balance.

Other: Dietary intervention of normal protein intake

Interventions

Dietary intervention of reduced protein intake OTHER

6-wk dietary intervention of reduced protein intake

Reduced protein diet

Dietary intervention of normal protein intake OTHER

6-wk dietary intervention of normal protein intake

Normal protein diet

Eligibility Criteria

• Age: 20 Years - 50 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Endurance athlete
• Exercising at least 10hrs per week
• Habitual dietary protein intake \~2g/kg body mass
• BMI\<25

You may not qualify if:

• Food allergies that exclude the controlled diet
• Inconsistent endurance training load

Sponsors & Collaborators

• University of Copenhagen: lead
• Maastricht University Medical Center: collaborator

Study Sites (1)

University of Copenhagen

Copenhagen, 2100, Denmark

Location

MeSH Terms

Conditions

Protein Deficiency

Condition Hierarchy (Ancestors)

Deficiency Diseases; Malnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases

Study Officials

• Nicki W Almquist, Post Doc

  University of Copenhagen

  STUDY DIRECTOR

• Bente Kiens, Professor

  University of Copenhagen

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor of Exercise, Nutrition and Metabolism, D Sci, PhD, Principal Investigator

Model Details: A pair-matched group, parallel design within each sex

Study Record Dates

• First Submitted: September 22, 2021
• First Posted: June 22, 2022
• Study Start: February 23, 2021
• Primary Completion: December 31, 2024
• Study Completion: December 31, 2025
• Last Updated: May 7, 2024

Record last verified: 2024-05

Data Sharing

• IPD Sharing: Will not share

Locations

DK (1)