Unravelling Energy Issues Underpinning Low Energy Availability in High Performance Athletes

NCT07026175 · tracked via the Priya Life Science Australia tracker

Sponsor

Australian Catholic University

Phase

Not applicable

Started

2025-09-04

Last updated

2026-08-13

Condition(s) studied

Relative Energy Deficiency in Sport

Investigational drug(s) / intervention(s)

Diet-induced low energy availabilityExercise-induced low energy availability

Diet-induced low energy availability: 6-days of severe low energy availability (LEA, 15kcal/kg FFM/d), achieved by superimposing restricted energy intake on the control trial.

Exercise-induced low energy availability: 6-days of severe low energy availability (LEA, 15kcal/kg FFM/d), achieved by superimposing increased exercise energy expenditure on the control trial.

Study summary

The goal of this clinical trial is to understand how the body responds to short-term, severe low energy availability (LEA) in healthy, weight-bearing endurance athletes aged 18-45 years old. LEA describes a mismatch between an individual's dietary energy intake and the energy cost of their commitments for training and competition. The main questions this trial aims to answer are:

1. What effect does short-term, severe LEA have on sleeping metabolic rate?
2. What effect does short-term, severe LEA have on other body systems identified within the Relative Energy Deficiency in Sport (REDs) Health and Performance Conceptual models?

Researchers will compare a control trial with both a LEA trial achieved through diet restriction and a LEA trial achieved through increased exercise to see if there are differences in the body's response.

Participants will complete three 6-day trials, a minimum of 3-weeks apart, involving:

* Prescribed diet (all food provided)
* Prescribed running and/or cycling exercise
* Two visits to ACU Fitzroy campus for blood tests and exercise testing
* 50 hour stay (two nights and two days) in the ACU metabolic chamber

Eligibility

Sex

ALL

Min age

18 Years

Max age

45 Years

Healthy volunteers

Accepted

Inclusion Criteria: * 18-45 years old * Well trained weight-bearing athlete (tier 2-4 1) * Perform \~45km per week of weight-bearing endurance training, and able to undertake the prescribed exercise in each trial condition * Pass the ESSA pre-exercise screening tool and/or obtain GP clearance to exercise Exclusion Criteria: * Assessment of red status on the REDs Clinical Assessment Tool * Unable to attend ACU in Fitzroy, Victoria, for the 6 study visits for completion of the study protocol * Pregnancy * Use of hormonal contraceptive with the previous 3 months * Onset of peri/menopause

Primary outcome measure(s)

Sleeping metabolic rate between trials, measured using a human metabolic chamber on night 5 of each trial condition. — Night 5 of each trial condition from enrolment to the end of the third trial period.
The primary outcome is the within-participant and sex-based difference in Sleeping Metabolic Rate (SMR) across the three trial conditions. Analyses will also compare differences in SMR responses between sexes.

Trial sites (1)

Facility	City	Region	Status
Australian Catholic University	Fitzroy	Victoria	Recruiting

More Australian Catholic University trials in Australia

Comparison of Dietetics Support With and Without Continuous Glucose Monitoring in Individuals With Type 2 Diabetes. Active, not recruiting

Official registry record

This page summarises publicly available registry data for informational purposes — not medical advice. Eligibility is determined by each study team; patients should discuss participation with their clinician.

View NCT07026175 on ClinicalTrials.gov ↗ ← All trials in Australia