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.