Active not recruitingNAINTERVENTIONAL

A 60 Days Head Down Tilt Bedrest With Artificial Gravity and Cycling Exercise on 24 Healthy Male (BRACE)

This study aims to understand how 60 days of lying slightly head-down affects the bodies of healthy men. This position mimics some of the health changes astronauts experience in space. They will compare two groups: one doing cycling exercise with added artificial gravity (like a spinning ride) and another doing just cycling. The main goal is to see if these exercises can prevent or reduce issues like weak bones and muscles, heart problems, or changes to vision. Researchers will check many body systems, including your heart, muscles, and immune system. The results could help future astronauts stay healthier during long space missions.

At a glance

Status

Active not recruiting

Phase

Sponsor

Centre National d'Etudes Spatiales

Enrolment target

Start

06 Feb 2023

Estimated completion

30 Apr 2026

Simulated Microgravity by Head Down Tilt Bedrest Weightlessness

What is this study about?

Imagine spending 60 days in bed, lying with your head slightly lower than your feet – that's what participants in this study will do! This position is used to safely mimic some of the changes that astronauts experience when living in space without gravity. When astronauts are in space for a long time, their bodies can change in various ways, such as their bones and muscles becoming weaker, and their heart and balance systems being affected. More recently, doctors have also noticed that some astronauts develop eye problems after long space missions.

Because it's hard to do many experiments in space, this bed rest study on Earth helps scientists understand these body changes better. The main aim is to test if special exercises can help. Half the participants will do cycling exercises while also experiencing 'artificial gravity' – a spinning motion that gently pushes them down, similar to gravity. The other half will just do the cycling exercise. Researchers want to see if the combination of cycling and artificial gravity is more effective than cycling alone in keeping the participants healthy during the bed rest period.

Over the 60 days, experts will carefully check many different parts of the participants' bodies, like their heart and blood vessels, muscles and bones, how their body uses energy, their sight, blood, and immune system. The information gathered from this study will be incredibly valuable. It will help us understand how to keep astronauts healthy and strong during long trips into space, maybe even to places like Mars, and help them recover when they return to Earth.

Key takeaways

This study helps understand how the body reacts to conditions like space travel.
Participants spend 60 days lying with their head slightly lower than their feet.
Researchers are testing if cycling with 'artificial gravity' can prevent negative health effects.
It aims to improve astronaut health during long space missions.
Only healthy men aged 20-45 can participate.

Who may be eligible?

This study is looking for healthy men between the ages of 20 and 45. To be considered, you should be within a healthy weight range (not too heavy or too thin for your height) and be between 158 cm and 190 cm tall.

Before you can join, you will have a thorough health check-up. This is to make sure you don't have any long-term illnesses, recent infections, heart problems, nerve issues, or problems with your ears, nose, throat, or bones. You also need to be a non-smoker, not use drugs or alcohol regularly, and be mentally fit after a special assessment. Your physical fitness will also be checked.

If you have a history of certain problems like chronic back pain, heart rhythm issues, high blood pressure, glaucoma, severe headaches (migraines), or some digestive or thyroid conditions, you won't be able to take part. This is because these conditions could either affect the study results or put your health at risk during the challenging bed rest period.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you a healthy man between 20 and 45 years old?
Are you within a healthy weight range and between 158-190 cm tall?
Do you have any long-term health conditions or recent serious illnesses?
Are you a non-smoker and do not use drugs or alcohol regularly?
Are you able to commit to 60 days of bed rest and follow-up appointments?

Answer every question to see your result.

What does participation involve?

If you take part in this study, you will spend 60 days continuously in bed, with your head tilted slightly downwards. During this time, you will be part of a control group (doing no special exercise) or one of two exercise groups: one doing cycling with artificial gravity, and another doing cycling alone. You will undergo many medical tests and measurements throughout the 60 days, including checks of your heart, muscles, bones, blood, and eyesight. These assessments will help researchers understand how your body is changing. There will also be a period before and after the 60 days for initial checks and follow-up assessments to see how your body recovers. The total duration of your involvement will therefore be longer than just the 60 days of bed rest, including preparation and recovery phases.

Potential risks and benefits

Participating in this study could potentially benefit future astronauts by helping develop ways to keep them healthy in space. You would also receive comprehensive medical monitoring throughout the study. However, spending 60 days in bed, especially with your head tilted, can lead to some health changes like muscle weakness, bone loss, or changes to your heart and balance, similar to what astronauts experience. While the exercises are designed to reduce these effects, there's always a risk involved with prolonged bed rest. You have the right to withdraw from the study at any time, even if you have already started, without affecting your medical care.

Locations (1)

MEDES-Institut de Médecine et Physiologie Spatiale
Verified postcode
Toulouse, France

Common questions

Why do I have to lie head-down?

Lying with your head slightly lower than your feet helps researchers safely create some of the body changes that happen to astronauts when they are in space without gravity.

What is 'artificial gravity'?

Artificial gravity in this study involves a spinning motion that gently pushes you down, similar to the feeling of gravity, while you are doing cycling exercise.

Will this study make me weaker?

The goal of the study is to see if the exercises can *prevent* or *reduce* weakening, but prolonged bed rest can have effects on your body. Your health will be closely monitored.

How long will I be involved in total?

You will spend 60 days in bed, but there will be additional time before and after for check-ups and to see how your body recovers. The full duration will be explained to you.

Can women take part?

No, this particular study is specifically looking for healthy male volunteers only. Other studies might include women.