NCT03845569

Influence of Habitual Protein Intake on AA Tracer Oxidation

Impact of Habitual Protein Intake on Estimates of Dietary Protein Requirements in Resistance Trained Athletes

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 5 (actual)
• Sponsor: University of Toronto · Academic / Other
• Sex: Male
• Age: 18 Years – 35 Years
• Healthy volunteers: Accepted

Summary

Protein is an essential nutrient that one's diet to maintain important bodily functions and to recover from exercise. Currently, the Indicator Amino Acid Oxidation method (IAAO) has been used to determine protein requirements in a variety of populations including children, neonates, the elderly and recently, resistance trained populations. This study serves to test the robustness of the IAAO method and to determine if high habitual dietary protein intake, as seen in resistance trained males, has the potential to influence the protein requirements determined by the IAAO method. Further, the current study also aims to determine how the body metabolizes or uses dietary protein and how it might change when consuming a protein intake that is less than what is habitually consumed.

Detailed description

This study employed a two-phase randomized crossover design, where participants performed both a High/Habitual protein phase and a moderate protein phase. The Habitual protein phase is designed to model resistance trained individual's habitual protein consumption by providing 2.2g/kg/d in a controlled diet. The Moderate protein phase is designed to investigate the impact of decreasing dietary protein intake to a moderate amount (1.2g/kg/d) over five days on protein metabolism. Both phases used the stable isotope L-\[1-13C\]Phenylalanine and metabolic trails were modelled after the indicator amino acid oxidation (IAAO) technique. High Protein Phase The high protein phase is three days in length, with diet-controlled throughout, and a metabolic trail on day 3. Participants will perform whole-body resistance exercise on days one and three. Moderate protein phase The Moderate protein phase is seven days in length, with MT on days three, five and seven. Dietary intake will be controlled throughout the whole phase providing either 2.2 g/kg/d of protein (days one and two), or 1.2 g/kg/d (days three through seven). Full body resistance exercise will be performed performed on days one, three, five and seven. This phase will allow measurement of protein metabolism over five days following a decrease in dietary protein intake, and to determine the effect of dietary changes on the IAAO method.

Conditions

• Protein/Amino Acid Metabolism
• Indicator Amino Acid Oxidation Method

Interventions

Type	Name	Description
OTHER	Dietary protein intake reduction	Following two days of controlled diet at 2.2g/kg/d of dietary protein, intake was reduced to 1.2g/kg/d for five days, and protein metabolism was measured on days 1, 3, and 5.
OTHER	Three day Controlled Diet	Three days of a controlled diet providing 2.2g/kg/d of dietary protein with protein metabolism measured on day 3. This was used to model the habitual intake of this cohort.

Timeline

• Start date: 2017-11-01
• Primary completion: 2018-04-18
• Completion: 2018-04-18
• First posted: 2019-02-19
• Last updated: 2019-02-19

Locations

1 site across 1 country: Canada