A New Nutritional Countermeasure to Prevent the Deconditioning Induced by 60 Days of Antiorthostatic Bed Rest

The objective of this study is to investigate whether the cocktail of natural antioxidants XXS-2A-BR2 comprising vitamin E and coupled with omega-3 helps to prevent and / or reduce the deleterious effects induced by long term physical inactivity through antiorthostatic bedrest. During a randomized 60 day bed rest study in 20 healthy male adults the two following aims will be undertaken:

* Sixteen scientific protocols will assess the changes in the cardiovascular, metabolism, muscle, bone, neuro sensorial, hematological and immunology systems.
* In the above mentioned systems, the potential beneficial effects of the countermeasure protocol will also be investigated.

Space flights have shown the possibilities and limitations of human adaptation to space. For the last 50 years, results showed that the space environment and microgravity in particular, cause changes that may affect the performance of astronauts. These physiological changes particularly challenge the cardiovascular, metabolic, muscle and bone functions. Space agencies regularly conduct simulations on the ground on healthy volunteers to mimic the effects of weightlessness (head down bed rest model) to better understand the mechanisms of adaptations of the organism to space, and develop ways to prevent and / or reduce the negative biological effects of microgravity on astronauts. These protocols are called countermeasures. Since the beginning of space missions, various countermeasures have been tested on the ground and in-flight, including different exercise protocols. To date, however, none has been entirely satisfactory and space agencies continue to conduct simulation studies to evaluate new countermeasures. Nowadays, the human spaceflight program has entered the next phase of space exploration towards the Moon and Mars and there are clearly inherent medical challenges with such a goal, among which, countermeasure developments are a clear priority.

Based on recent evidences, the next countermeasure to be tested during a 60-day bed rest includes a nutritional countermeasure composed of an anti-oxidant and anti-inflammatory dietary mix.

Eligibility Criteria:
Inclusion Criteria:

* Healthy male volunteer (see below the description of medical tests and laboratory analysis performed at the selection visit),
* Age 20 to 45,
* No overweight nor excessive thinness with BMI (weight Kg/ height m2) between 22 and 27,
* Height between 158 and 190 cm,
* No personal nor family past record of chronic or acute disease or psychological disturbances which could affect the physiological data and/or create a risk for the subject during the experiment,
* Fitness level assessment:

  * if age \< 35 years: 35 ml/min./kg \< VO2max \< 60ml/min./kg,
  * if age \> 35 years: 30 ml/min./kg \< VO2max \< 60ml/min./kg
* Active and free from any orthopedic, musculoskeletal and cardiovascular disorders,
* Non smokers,
* No alcohol, no drug dependence and no medical treatment,
* No shift work or travel across more than one time zone in previous 2 months,
* Covered by a Social Security system,
* Have signed the information consent,
* Free of any engagement during the three hospitalization planned periods.

Exclusion Criteria:

* - Past record of orthostatic intolerance,
* Cardiac rhythm disorders,
* Chronic back pains,
* History of hiatus hernia or gastro-esophageal reflux,
* History of thyroid dysfunction, renal stones, diabetes, migraines,
* Past records of thrombophlebitis, family history of thrombosis or positive response in thrombosis screening procedure,
* Allergy including xylocaine allergy
* Abnormal result for lower limbs echo-doppler,
* History or active claustrophobia,
* History of genetic muscle and bone diseases of any kind,
* History of sleep disorders, no shift work or travel across more than one time zone in previous two months
* Vestibular disorders,
* Audition problem,
* Vision corrected no more than 20/30, color-blindness
* Bone mineral density: T-score ≤ -1.5,
* Osteosynthesis material, presence of metallic implants,
* History of knee problems or joint surgery/broken leg
* Poor tolerance to blood sampling,
* Having given blood (more than 8ml/kg) in a period of 8 weeks or less before the start of the experiment,
* Special food diet, vegetarian or vegan, food allergy especially allergic to peanut or soya.
* Positive reaction to any of the following tests: HVA IgM (hepatitis A), HBs antigen (hepatitis B), anti-HVC antibodies (hepatitis C), anti-HIV1+2 antibodies,
* Subject already participating or in the exclusion period of a clinical research,
* Refusal to give permission to contact his general practitioner,
* Incarcerated persons,
* Subject who, in the judgment of the investigator, is likely to be non-compliant during the study, or unable to cooperate because of a language problem or poor mental development,
* Subject who has received more than 4500 Euros within 12 months for being a research subject.
* Subject under guardianship or trusteeship.