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Recruiting Not applicable Interventional Accepts healthy volunteers

Timing of Energy Availability on Menstrual Cycle Function

ClinicalTrials.gov ID: NCT06471582

Public ClinicalTrials.gov record NCT06471582. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 6, 2026, 1:19 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

Implications for the Timing of Energy Availability on Menstrual Cycle Function

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

The primary aim of this clinical trial is to evaluate how fasted prolonged exercise may influence circulating reproductive hormones (i.e., estradiol, progesterone, luteinizing hormone) and menstrual cycle length when energy availability is maintained at or above 30 kcal/kg lean body mass/ day among women who regularly do running or cycling exercise. A secondary aim is to determine the effects of fasted prolonged exercise on serum leptin and cortisol. Participants will be asked to do the following over a \~3 month enrollment period: * attend a laboratory visit at the beginning of the study to have their resting metabolic rate, aerobic fitness, and body composition tested * monitor their menstrual cycle length, urine hormones, perceived stress levels, and diet for \~3 months * complete 3, 90-minute exercise sessions on a stationary bike or treadmill either fed (consuming a carbohydrate meal 1 h prior and 0.7 g carbohydrate/ kg body mass/ h during exercise) or fasted (consuming no meal prior and no carbohydrates during exercise) during month \~3 * saliva samples will be taken prior to and after 90-minute exercise sessions for quantification of leptin and cortisol

Study identification

NCT ID
NCT06471582
Recruitment status
Recruiting
Study type
Interventional
Phase
Not applicable
Enrollment
64 participants

Conditions and interventions

Interventions

Dietary Supplement

Eligibility (public fields only)

Age range
18 Years to 40 Years
Sex
Female
Healthy volunteers
Accepts healthy volunteers

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Jul 31, 2024
Primary completion
Aug 30, 2027
Completion
Aug 30, 2027
Last update posted
Apr 30, 2026

2024 – 2027

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
William J. Hybl Sports Medicine and Performance Center Colorado Springs Colorado 80918 Recruiting

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT06471582, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Apr 30, 2026 · Synced Sep 6, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT06471582 live on ClinicalTrials.gov.

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