Alternative Treatments in Acute Mountain Sickness

The purpose of this research is to support a hypothesis that osteopathic manual medicine (OMM) and / or a 10 cmH2O end-expiratory pressure (PEEP) could be used in the prevention of acute mountain sickness (AMS). During altitude exposure, an exaggerated hypoxemia and the increase of intracranial pressure are both known to be major physipathological ways of AMS development. The goal of the osteopathic protocol is to release tension on the circulatory structures directly related to cranial circulation and drainage. The main hypothesis is that it could lead to lower intracranial pressure and help reducing AMS signs. Furthermore the investigators would like to define a osteopathic score for individual AMS sensitivity, based on cranial bones mobility. Several studies have shown that using PEEP at altitude (or hypoxia) increases SpO2. As for osteopathy protocol, the investigators would like to apply this experimental condition during real altitude exposure in a randomized controlled protocol.