Protein Requirements in Resistance Trained Females

March 28, 2019 updated by: Daniel Moore, University of Toronto
In this study, the investigators will use the minimally invasive indicator amino acid oxidation (IAAO) technique to determine protein requirements in weight-trained males. It is hypothesized that the present study will show that protein requirements for weight-trained females are i) greater than the current RDA for non-active individual's comparable estimates, and ii) greater than existing nitrogen balance-based estimates for weight-training individuals

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Provided that energy needs are met, the adequate ingestion of dietary amino acids is the most critical nutritional factor to support the optimal remodeling and deposition of lean body mass in individuals of all ages. Current recommendations according to the World Health Organization/Food and Agricultural Organization suggest that daily protein requirements in healthy, non-active adults are 0.8 g/kg/day. However, of primary interest in the present study is the impact that exercise has on the nutritional requirement for dietary amino acids in highly active adults - e.g., individuals performing weight training. Protein requirements for individuals who participate in strength-based exercise training have been suggested to range from 1.2-1.7g protein/kg/day (Rodriguez et al., 2009; Tarnopolsky, 1992; Phillips et al., 2007), which equates to a 50-112% increase from the current RDA. The increased requirement in this population may reflect the requirement for protein to repair/rebuild lean tissues by promoting anabolism (Phillips, 2004). Nutritional requirements for dietary amino acids in adults (both active and non-active) have traditionally been determined utilizing the antiquated and often erroneous nitrogen balance technique (Costaneda et al., 1995; Campbell et al., 1984), which is prone to underestimating protein requirements and therefore provides challenges to making accurate nutritional recommendations (Humayun, Elango, Ball, and Pencharz, 2007). This observation that nitrogen balance underestimates protein requirements in non-active individuals could suggest that protein requirements are much greater than the current WHO/FAO recommendation of 0.8 g/kg/day which was evaluated using the nitrogen balance technique (Rand, Pellett and Young, 2003). As a result, there is a need to re-evaluate recommendations utilizing advanced stable isotope methodology in order to characterize how dietary amino acid needs may be modulated by physical activity. Recent studies using the minimally invasive indicator amino acid oxidation (IAAO) technique have suggested that protein requirements in young men are at least 50% higher than WHO/FAO guidelines based on nitrogen balance data (Humayun, Elango, Ball, and Pencharz, 2007). Furthermore, resistance training has been reported to increase (according to nitrogen balance methodology) protein requirements by up to 75% Tarnopolsky et al., 1992). Therefore, in this study, the investigators will use the IAAO technique to determine protein requirements in weight-trained males. It is hypothesized that the present study will show that protein requirements for weight-trained females are i) greater than the current RDA for non-active individual's comparable estimates, and ii) greater than existing nitrogen balance-based estimates for weight-training individuals.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
8

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 35 years (Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

Female

Description

Inclusion Criteria:

  • healthy female weight-trained individuals that have trained consistently for >1 year
  • complete a physical activity readiness questionnaire (PAR-Q+)
  • Train each muscle group (i.e. chest, back, legs) at least twice a week
  • Meets strength relative to body weight GUIDELINES adapted from Morton et al., 2016; Chilibeck et al., 1997 (sex specific).

Bench Press:

body weight (kg)*0.7

Leg Press:

body weight (kg)*2.3

Exclusion Criteria:

  • sedentary for greater than 1 month in the last 6 months prior to the study
  • non-weight stable for the past month
  • smoker
  • Illicit drug use (e.g. growth hormone, testosterone, etc.)
  • Individual plans to increase or decrease body mass in the next 3 months
  • Habitually ingests greater than or equal to 3g protein kg/bw/day
  • Use of supplements such as creatine and beta-alanine in the last 30 days.
  • Hormone-based birth control. Hormonal fluctuations associated with the menstrual cycle have been reported to alter protein metabolism during exercise (Hamadeh, Devries, and Tarnopolsky, 2005) For this reason, the following exclusion criteria will be applied to female participants only: use of birth control and discontinued use within last 3 months
  • Inability to adhere to any of the protocol guidelines

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Healthy females
All participants receive the intervention: Protein intake (dose). This consists of varying levels of dietary protein intakes, in the form of crystalline amino acids, ranging from 0.2-3.0 g/kg/d
Other: Protein intake (dose)
Protein intake, in the form of crystalline amino acids, will range between 0.2-3.0 g/kg/d

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Phenylalanine oxidation
Time Frame: Through study completion: an average of 6 metabolic trials (days), each separated by approximately 1 week
In µmol/kg/h, the product of F13CO2 and VCO2. F13CO2 is determined via breath enrichment analysis of 13CO2 after 1-13C phenylalanine ingestion, and VCO2 is determined via indirect calorimetry
Through study completion: an average of 6 metabolic trials (days), each separated by approximately 1 week

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Phenylalanine rate of appearance
Time Frame: Through study completion: an average of 6 metabolic trials (days), each separated by approximately 1 week
In µmol/kg/h; calculated from urine analysis of1-13C Phe enrichment
Through study completion: an average of 6 metabolic trials (days), each separated by approximately 1 week
Net protein balance
Time Frame: Through study completion: an average of 6 metabolic trials (days), each separated by approximately 1 week
In µmol/kg/h; calculated as the difference between whole body net protein synthesis and protein breakdown
Through study completion: an average of 6 metabolic trials (days), each separated by approximately 1 week

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Toronto

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
November 1, 2016

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
October 6, 2017

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
November 30, 2018

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
January 5, 2018

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 5, 2018

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
January 11, 2018

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
March 29, 2019

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
March 28, 2019

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
March 1, 2019

More Information

Terms related to this study

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • RTF

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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings