CompletedNot Applicable

Integrative Study of Physiological Changes Induced by a 5-Day Dry Immersion on 20 Healthy Female Volunteers (DI5-Women)

France20 participantsStarted 2021-08-24

Plain-language summary

Dry immersion (DI) is a ground-based model of prolonged conditions of simulated microgravity. Dry immersion involves immersing the subject in water covered with an elastic waterproof fabric. As a result, the immersed subject, who is freely suspended in the water mass, remains dry. Within a relatively short duration, the model can faithfully reproduce most physiological effects of actual microgravity, including centralization of body fluids, support unloading, and hypokinesia. The objective of the study is to evaluate the physiological changes induced by 5 days of dry immersion in the female organism. The main physiological systems will be explored before, during and after the 5 days of immersion through a battery of specific tests and measurements. The results will be analyzed by scientists specializing in each field in order to better understand the dry immersion model, to compare its effects with those of the bedrest model and those of spaceflight. The clinical (adverse effects, comfort of subjects) and operational aspects are also part of the secondary objectives of the study.

Who can participate

Age range

20 Years – 40 Years

Sex

FEMALE

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Healthy female volunteer (see below the description of medical tests and laboratory analysis performed at the selection visit), * Age 20 to 40, * No overweight nor excessive thinness with BMI (weight Kg/ height m2) between 20 and 26, * Height between 158cm and 180 cm, * Regular menstrual cycles and cycles lasting between 20 and 35 days, * Without oestroprogestative contraception (i.e., oral progestative contraception, IUDs, implants or absence of contraception are allowed), * Certified as healthy by a comprehensive clinical assessment (detailed medical history and complete physical examination): in particular, free from any chronic disease or any acute infectious disease or cardiovascular, neurological, ENT (especially orthostatic hypotension and vestibular disorders), orthopaedic or musculoskeletal disorders, * Fitness level assessment: * if age \< 35 years: 35 ml/min./kg \< VO2max \< 55 ml/min./kg, * if age \> 35 years: 30 ml/min./kg \< VO2max \< 55 ml/min./kg, * Non active smokers, * No alcohol, or drug addiction, and no medical treatment (with the exception of the aforementioned accepted means of contraception), * Covered by a Health Insurance System, * Having signed the informed consent, * Free from any engagement during the study. Exclusion Criteria: * Any history or presence of clinically relevant cardiovascular, neurological or ENT (especially orthostatic hypotension and vestibular disorders), any chronic disease; any acute infectious dis…

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Change in orthostatic tolerance

Timeframe: At baseline and after five days of dry immersion

Change in peak aerobic power (VO2max test)

Timeframe: At baseline and after five days of dry immersion

Change in plasma volume

Timeframe: At baseline and after five days of dry immersion

Change in fluid shift distribution towards the cephalic region

Timeframe: At baseline, the first day to quantify the short term effect and the fifth day of dry-immersion to quantify the long term effect of fluid shift

Change in vascular endothelium integrity

Timeframe: At baseline and during the five days of the dry-immersion period

Change in circadian rhythms of blood pressure

Timeframe: At baseline and during the five days of the dry-immersion period

Change in lower limb veins functions

Trial details

NCT IDNCT05043974

SponsorCentre National d'Etudes Spatiales

Sponsor typeOTHER_GOV

Study typeINTERVENTIONAL

Primary completion2021-12-08

View on ClinicalTrials.gov More Weightlessness trials

Plain-language summary

Who can participate

Age range

20 Years – 40 Years

Sex

FEMALE

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

What they're measuring

Change in orthostatic tolerance

Timeframe: At baseline and after five days of dry immersion

Change in peak aerobic power (VO2max test)

Timeframe: At baseline and after five days of dry immersion

Change in plasma volume

Timeframe: At baseline and after five days of dry immersion

Change in fluid shift distribution towards the cephalic region

Timeframe: At baseline, the first day to quantify the short term effect and the fifth day of dry-immersion to quantify the long term effect of fluid shift

Change in vascular endothelium integrity

Timeframe: At baseline and during the five days of the dry-immersion period

Change in circadian rhythms of blood pressure

Timeframe: At baseline and during the five days of the dry-immersion period

Change in lower limb veins functions