Clinical trial NCT06961773: Bone Metabolism in Premenopausal Exercising Women
Official title: Bone Metabolism in Exercising WOMEN: Influence of Low Energy Availability and Sex Hormone Fluctuations
Study type: INTERVENTIONAL
Overall status: ENROLLING_BY_INVITATION
Phase: NA
Conditions: Contraception
Bone Metabolism
Low Energy Availability
Eumenorrhea
Lead sponsor: Universidad Politecnica de Madrid
Sponsor class: OTHER
First posted: 2025-05-08
Enrollment: 22
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 30
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: BASIC_SCIENCE

Brief summary: The main goal of this study is to examine how sex hormones and low energy availability affect the concentrations of bone remodelling markers at rest and after a running protocol. The research questions to be addressed are:

1: Does the ovarian hormone profile influence serum bone marker concentrations in women exercising resting and in response to to exercise?

2. Are there differences in response to low energy availability in bone marker concentrations between eumenorrhoeic female athletes and oral contraceptive users?

3: Is the response of bone markers affected by different exercise stimuli: endurance or aerobic endurance?

4: Do bone markers return to baseline levels after 24 hours of high energy availability diet after 6 days of low energy availability?

Detailed description: To achieve the aim of the study, there will be two experimental groups - e.g. eumenorrhoeic females and oral contraceptive users - who, after screening, will be randomly assigned to a low- or high-energy diet. After 6 days on this diet, the participant will undergo an intervallic running protocol and blood samples will be taken before and after the test. The following month the participant will do the other type of diet.

Eligibility criteria: Inclusion Criteria:

* Be healthy and between 18 and 30 years old.
* Engage in endurance sports that involve running (such as athletics, running, triathlon, trail running, etc.) for 3 to 12 hours per week..
* Eumenorrheic females with regular menstruation at least 6 months prior to the study.
* Monophasic oral contraceptive users at least 6 months prior to the study.

Exclusion Criteria:

* Amenorrheic females.
* Pregnant females.
* Affected by any disorder related to the hypothalamo-pituitary-ovarian axis.
* Having suffered a bone fracture in the year before the study.
* Taking any medication or supplements that affect bone metabolism.

Primary outcomes:
measure: Concentration of bone metabolism biomarkers
timeFrame: immediately pre-exercise and immediately, 15 minutes and 24 hours post-exercise
measure: Concentrations of other biochemical biomarkers
timeFrame: Immediately pre-exercise and immediately, 15 minutes and 24 hours post-exercise
measure: Concentrations of sex hormones
timeFrame: Immediately pre-exercise and immediately, 15 minutes and 24 hours post-exercise
measure: Bone mineral density
timeFrame: At the screening phase
Secondary outcomes:
measure: Training status variables
timeFrame: At the screening phase
measure: Body composition variables
timeFrame: Immediately pre- and post-nutritional intervention (bioimpedance) and DXA at the screening
measure: Body metrics
timeFrame: Measured at the screening phase
Other outcomes:
Locations:
city: Madrid
country: Spain
facility: Faculty of physical activity and sport sciences
state: Comunity of Madrid
Study officials:
References: