Bone Metabolism, Contraception, Eumenorrhea, Low Energy Availability
Conditions
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.
Interventions
OTHERLow energy availability
Participants follow 6 days of a low-energy availability diet. The kilocalories of each diet are prescribed individually based on their fat-free mass.
OTHERHigh energy availability
Participants follow 6 days of a high-energy availability diet. The kilocalories of each diet are prescribed individually based on their fat-free mass.
Sponsors
Universidad Politecnica de Madrid
Study design
Allocation
NON_RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 30 Years
Healthy volunteers
Yes
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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Concentration of bone metabolism biomarkers | immediately pre-exercise and immediately, 15 minutes and 24 hours post-exercise | Concentration of procollagen type I N-propeptide (P1NP), cross-linking telopeptide of type I collagen (βCTX-1), paratyroid hormone, calcium, sclerostin, osteoprotegin, osteocalcin, bone alkaline phospatase, Receptor Activator for Nuclear Factor κ B Ligand (RANKL) measured in serum samples. |
| Concentrations of other biochemical biomarkers | Immediately pre-exercise and immediately, 15 minutes and 24 hours post-exercise | Concentrations of Triiodothyronine (T3), Albumin, Sex Hormone Binding Globulin (SHBG), etc. measured in serum |
| Concentrations of sex hormones | Immediately pre-exercise and immediately, 15 minutes and 24 hours post-exercise | Concentrations of 17β-Oestradiol and Progesterone measured in serum. |
| Bone mineral density | At the screening phase | Total, lumbar spine and femoral neck bone mineral density (g/cm\^2) measured by dual x-ray absorptiometry |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Body composition variables | Immediately pre- and post-nutritional intervention (bioimpedance) and DXA at the screening | Fat mass (kg), fat free mass (kg), fat mass percentage, fat-free mass percentage (FFM), total mass (kg) measured by dual x-ray absorptiometry |
| Body metrics | Measured at the screening phase | Height (cm) |
| Training status variables | At the screening phase | Oxygen uptake at ventilatory threshold 1, ventilatory threshold 2, and maximal oxygen uptake (ml/kg/min) measured with a gas analyser. |
Countries
Spain
Outcome results
None listed