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Substrate Utilization and Hormonal Status in Women

This study has been completed.
French Federation of Physical Education and Gymnastic (EPGV)
Information provided by:
University Hospital, Clermont-Ferrand Identifier:
First received: February 16, 2010
Last updated: January 18, 2011
Last verified: January 2011

Women sexual hormones (i.e. estrogen) are involved in the regulation of substrate utilization and storage. Being under oral contraception (OC) may conduct to metabolic and hormonal modifications, but results are confused regarding the impact on substrate utilization. In the present study, the aim is then to explore the effect of hormonal status on substrate utilization during sous-maximal exercise, comparing women with and without OC.

We hypothesised that women under OC have a lower Respiratory Exchange Ratio (RER) at exercise than women without contraception underlying a greater reliance on fat oxidation.

Substrate Utilization

Study Type: Observational
Official Title: Impact of Women Hormonal Status (Oral Contraception vs no Contraception) on Substrate Utilization During Exercise

Resource links provided by NLM:

Further study details as provided by University Hospital, Clermont-Ferrand:

Primary Outcome Measures:
  • Substrate utilization will be the main outcome under study.For each volunteer, it will be assessed during exercise (between 12h and 12h45) for the 2 experimental conditions with exercise [ Time Frame: during exercise (between 12h and 12h45) ]

    Substrate utilization:

    The Respiratory Exchange Ratio (RER) that corresponds to carbon dioxide production divided by oxygen consumption (VCO2/VO2) will be used to determine the energetic substrate used during exercise. This RER will be obtained, in continuous, thanks to an indirect calorimetric system composed of a breath by breath gas analyzer. A RER closed to 0.7 illustrates lipid utilization while carbohydrate use will correspond to a RER that reached 1.

Secondary Outcome Measures:
  • The hormonal regulation involved in substrate utilization. It will be assessed during the 3 experimental conditions during all the experimental day: - Breakfast + exercise - Exercise alone - Breakfast alone [ Time Frame: before (8h, 8h45), during (12h, 12h20, 12h30, 12h45) and after exercise (13h15, 13h45; 14h45) ]

    The hormonal regulations involved in the substrate utilization will be assessed thanks to blood samples collected before, during and after exercise.

    At each blood collection, the nurses will collect a EDTA tube (5ml) used to assess free fatty acid and glycerol; and 2 heparin ones (2*5ml) to assess 17β-œstradiol, progesterone, triglycerides, cholesterol, HDL-C, LDL-C, glucose, insulin, growth hormone, IGF-I, IGFBP-1, IGFBP-3, adrenaline, noradrenaline, Atrial Natriuretic Peptide, and C-Reactive Protein.

Estimated Enrollment: 24
Study Start Date: February 2010
Study Completion Date: November 2010
Primary Completion Date: November 2010 (Final data collection date for primary outcome measure)
12 women with oral contraception
12 women without any contraception

Detailed Description:

24 healthy young women (12 with OC and 12 without any contraception) will complete a maximal test on an ergometer cycle to obtain their maximal oxygen consumption (VO2max).Their body composition will be assessed by DXA. They will be asked to complete 3 experimental sessions.

During a first session the volunteers will remain inactive, and only a breakfast will be offered. During the second session, a breakfast will be offered and they will have to complete a sub-maximal exercise set at 60% of their VO2max 3 hours after breakfast. And the third session will consist in the realisation of exercise on fast state. Those three sessions will be realized in a randomized order. Several blood (catheter) and salivary samples will be collected during the three sessions, throughout the experimental day.


Ages Eligible for Study:   19 Years to 30 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes
Sampling Method:   Probability Sample
Study Population
24 healthy young women (12 with OC and 12 without any contraception) will complete a maximal test on an ergometer cycle to obtain their maximal oxygen consumption (VO2max).Their body composition will be assessed by DXA. They will be asked to complete 3 experimental sessions

Inclusion Criteria:

  • Female
  • Adults between 19 to 30 years old
  • Body mass index between 20 and 25 kg.m-²
  • Oral contraception (half of the sample) : mini-dosed, and mono-phasic, ethinyl estradiol ≤ 30 µg
  • Without contraception (half of the sample)
  • Affiliated to National Health Insurance
  • Subject giving her written informed consent
  • Subject considered as normal after clinical examination and medical questionnaire.

Exclusion Criteria:

  • Chronic pathologies : cardiovascular diseases, cancer, chronic inflammation diseases, renal, intestinal impairments
  • Refusal to be registered on the National Volunteers Data file
  • Being in exclusion on the National Volunteers Data file
  • Practising intensive physical exercise
  • Heavy consumer of alcohol or/and tobacco
  • Previous medical and/or surgery judged by the investigator as incompatible with this study
  • Pregnancy
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Please refer to this study by its identifier: NCT01095614

CHU Clermont-Ferrand
Clermont-Ferrand, France, 63003
Sponsors and Collaborators
University Hospital, Clermont-Ferrand
French Federation of Physical Education and Gymnastic (EPGV)
Principal Investigator: Martine DUCLOS, Pr University Hospital, Clermont-Ferrand
  More Information

Responsible Party: Patrick LACARIN, CHU Clermont-Ferrand Identifier: NCT01095614     History of Changes
Other Study ID Numbers: CHU-0068
AU818 ( Other Identifier: CPP )
Study First Received: February 16, 2010
Last Updated: January 18, 2011

Keywords provided by University Hospital, Clermont-Ferrand:
Hormonal status
Substrate utilization
Women Hormonal Status (with oral contraception or without any contraception) processed this record on May 25, 2017