Recruiting

Observational Study

Sponsor:

University of Colorado, Colorado Springs

Code:

NCT05967819

Conditions

Amenorrhea Secondary

Eligibility Criteria

Sex: Female

Age: 18 - 35

Healthy Volunteers: Accepted

Interventions

Exercise Stress

Psychosocial Stress

Study Details

Brief summary:

The goal of this clinical trial is to determine how changes in exercise and psychosocial stress may influence the risk of menstrual cycle irregularities in female runners and cyclists. The main questions it aims to answer are:

  • Does the implementation of exercise or psychosocial stress effect circulating reproductive hormones (i.e., estradiol, progesterone, luteinizing hormone) and menstrual cycle length?
  • Is there an additive effect of combined exercise and psychosocial on circulating reproductive hormones (i.e., estradiol, progesterone, luteinizing hormone) and menstrual cycle length?

Participants will be asked to do the following over the \~3 month enrollment period:

  • attend a laboratory visit at the beginning and end of the study to have their resting metabolic rate, aerobic fitness, and body composition tested
  • monitor their menstrual cycle length, daily perceived stress levels, physical activity, and diet each month
  • provide several urine and saliva samples each month
  • either maintain their usual physical activity and lifestyle habits (control group), increase the duration of their weekly running or cycling mileage by 30% (exercise stress group), complete cognitive function tasks designed to be stressful (psychosocial stress group), or increase the duration of their weekly running or cycling mileage by 30% and complete cognitive function tasks designed to be stressful (exercise + psychosocial stress group) during the final month of enrollment.

Researchers will compare control, exercise stress, psychosocial stress, and exercise + psychosocial stress groups to see if there is an effect on circulating reproductive hormones (i.e., estradiol, progesterone, luteinizing hormone) and menstrual cycle length.

Conditions

Amenorrhea Secondary

Study ID

NCT05967819

Start date

Aug 9, 2023

Status verified date

Jan, 2026

Completion date

Aug 30, 2026

Anticipated

Primary completion date

Aug 30, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: Female

Age: 18 - 35

Healthy Volunteers: Accepted

Inclusion Criteria:

  • participates in structured running or cycling exercise for at least 30 minutes on 4 days per week or more
  • have regular periods every 21 to 35 days
  • have not used hormonal contraceptives for at least the past 6 months
  • are not currently or trying to become pregnant or are breastfeeding, and have not been pregnant or breastfeeding for the past 12 months
  • have never been diagnosed with a menstrual cycle disorder (e.g., menorrhagia, amenorrhea, dysmenorrhea, polycystic ovary syndrome \[PCOS\], endometriosis, premenstrual dysphoric disorder \[PMDD\], menstrual migraines, ovarian cancer, ovarian insufficiency, uterine or endometrial cancer)
  • have never been diagnosed with a metabolic disease (e.g., hypothyroidism, hyperthyroidism, Cushing disease, Addison's disease, diabetes)

Exclusion Criteria:

  • missing > 4 consecutive days of aerobic exercise (i.e., running, cycling, cross training) if assigned to the exercise intervention groups
  • they indicate they "Could not participate at all due to a health problem" or have had to modify their exercise training, felt their injury, illness, or other health problem has affected their exercise performance, or experienced symptoms/ health complaints greater than "To a minor extent" on the Oslo Sports Trauma Research Center Questionnaire (exercise training intervention group)
  • demonstrate clinical low energy availability as defined as energy availability <30 Kcal/kg fat free mass in the first two months of at-home monitoring
  • report menstrual cycle lengths <21 days or >35 days in the first two months of at-home monitoring
  • do not demonstrate an anticipated rise in progesterone levels during the latter half of their cycle and luteinizing hormone levels at mid-cycle compared to tests taken during the first few days after menses in the first two months of at-home monitoring
  • begin taking a hormonal contraceptive
  • become pregnant
  • are diagnosed with a menstrual cycle disorder (e.g., menorrhagia, amenorrhea, dysmenorrhea, polycystic ovary syndrome \[PCOS\], endometriosis, premenstrual dysphoric disorder \[PMDD\], menstrual migraines, ovarian cancer, ovarian insufficiency, uterine or endometrial cancer)
  • are diagnosed with a metabolic disease (e.g., hypothyroidism, hyperthyroidism, Cushing disease, Addison's disease, diabetes), 10) are diagnosed with a major cardiovascular disease, respiratory disease, or musculoskeletal injury
  • are unable to follow instructions for any of the procedures

Study Design

Enrollment

54 participants

Anticipated

Allocation

Randomized

Intervention Model

Factorial

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

no intervention: Control

Participants will be asked to maintain their usual physical activity and lifestyle habits.

experimental: Exercise Stress

The duration of participant's weekly running or cycling mileage will be increased by 30% while intensity is maintained.

experimental: Psychosocial Stress

Participants will be asked to complete cognitive function tasks designed to be stressful while maintaining their usual physical activity habits.

experimental: Exercise + Psychosocial Stress

Participants will be asked to complete cognitive function tasks designed to be stressful while the duration of their weekly running or cycling mileage is increased by 30% and intensity maintained.

Interventions

Exercise Stress

Increased exercise volume

Psychosocial Stress

cognitive tasks

Primary outcome measure

  • Urinary estrone-3-glucuronide (E3G) [ Time Frame: 3 months ]
  • Urinary pregnanediol glucuronide (PdG) [ Time Frame: 3 months ]
  • Urinary luteinizing hormone (LH) [ Time Frame: 3 months ]
  • Menstrual cycle length [ Time Frame: 3 months ]

Central Contacts and Locations

Central contacts

Marissa Baranauskas, PhD

719-255-4475mbaranau@uccs.edu

Kristen Rudd, PhD

krudd@uccs.edu

Locations

University of Colorado Colorado Springs

Recruiting

Colorado Springs, Colorado, United States, 80918

Contacts

Marissa Baranauskas, PhD

719-255-4475mbaranau@uccs.edu

Kristen Rudd, PhD

krudd@uccs.edu

Principal Investigator:

Marissa Baranauskas, PhD

More Information

Sponsor

University of Colorado, Colorado Springs

Last update posted

Jan 8, 2026

Last verified

Jan, 2026

Keywords

  • functional hypothalamic amenorrhea
  • menstrual cycle
  • female athlete

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of Colorado, Colorado Springs on 2026-01-08.