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Recruiting NCT06471582

NCT06471582 Timing of Energy Availability on Menstrual Cycle Function

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Clinical Trial Summary
NCT ID NCT06471582
Status Recruiting
Phase
Sponsor University of Colorado, Colorado Springs
Condition Menstrual Irregularity
Study Type INTERVENTIONAL
Enrollment 64 participants
Start Date 2024-08-01
Primary Completion 2027-08-31

Eligibility & Interventions

Sex Female only
Min Age 18 Years
Max Age 40 Years
Study Type INTERVENTIONAL
Interventions
Artificially Sweetened Carbohydrate BeverageArtificially Sweetened Beverage

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

This trial targets 64 participants in total. It began in 2024-08-01 with a primary completion date of 2027-08-31.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

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

Eligibility Criteria

Inclusion Criteria: * participates in structured running or cycling exercise for at least 30 minutes on 3 or more days per week * accustomed to exercising for 90 minutes or more * has regular periods every 21-35 days * have not taken hormonal contraceptives for at least the past 6 months * is not currently or trying to become pregnant or breastfeeding, and has not been pregnant or breastfeeding in the past 12 months * does not currently have a diagnosis of a major menstrual cycle disorder (i.e., amenorrhea, polycystic ovary syndrome \[PCOS\], endometriosis, ovarian cancer, ovarian insufficiency, uterine or endometrial cancer) * does not currently have a metabolic disease (i.e., hypothyroidism, hyperthyroidism, Cushing disease, Addison's disease, diabetes, congenital adrenal hyperplasia) * does not currently have a major cardiovascular or respiratory disease Exclusion Criteria: * miss more than 7 consecutive days of aerobic activity (i.e., running, cycling, cross training) * demonstrate clinical low energy availability as defined as energy availability \<30 kcal/kg fat free mass * report menstrual cycle lengths \<21 or \>35 days in the first 2 months of at-home monitoring * do not demonstrate an anticipated rise in luteinizing hormone and progesterone in the first 2 months of at-home monitoring * begin taking a hormonal contraceptive * become pregnant * are diagnosed with a menstrual cycle disorder (i.e., amenorrhea, polycystic ovary syndrome \[PCOS\], endometriosis, ovarian cancer, ovarian insufficiency, uterine, or endometrial cancer) * are diagnosed with a metabolic disease (i.e., hypothyroidism, hyperthyroidism, Cushing disease, Addison's disease, diabetes) * are diagnosed with a major cardiovascular or respiratory disease * are unable to follow instructions for any of the procedures

Contact & Investigator

Central Contact

Marissa Baranauskas, PhD

✉ mbaranau@uccs.edu

📞 719-255-4475

Frequently Asked Questions

Who can join the NCT06471582 clinical trial?

This trial is open to female participants only, aged 18 Years or older, up to 40 Years, studying Menstrual Irregularity. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

Is NCT06471582 currently recruiting?

Yes, NCT06471582 is actively recruiting participants. Contact the research team at mbaranau@uccs.edu for enrollment information.

Where is the NCT06471582 trial being conducted?

This trial is being conducted at Colorado Springs, United States.

Who is sponsoring the NCT06471582 clinical trial?

NCT06471582 is sponsored by University of Colorado, Colorado Springs. The trial plans to enroll 64 participants.

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