The Science of the Summits
A report on the research conducted by the Hypoxia Physiopathology laboratory in Grenoble. Destination Aiguille du Midi for a better understanding of how the body works at nearly 13,000 feet of altitude...
Suspended in a cable car 230 feet from the ground, Alexis is en route to an unusual experiment: he has volunteered to participate in a scientific study conducted at Aiguille du Midi, in the Alps, at 12,605 feet of altitude! Surrounding him are Petit Dru, the Aiguilles, and Mont Blanc – the roof of western Europe at 15,778 feet above sea level. A landscape that will take your breath away… but not just because of its beauty! Here the effects of altitude are already making themselves felt. Pressure here is lower than at sea level, meaning that each intake of air contains less oxygen (O2). To compensate this, the respiratory rate increases, causing breathlessness. A phenomenon referred to by specialists as hypoxia.
Each individual, irrespective of their condition, tolerates altitude differently. Every year, thousands of mountaineers develop altitude sickness, which can sometimes be fatal. Hypoxia can also affect sleep: breathing, qualified as periodic, is interspersed with apnea and micro-awakenings. For a better night’s sleep, some mountaineers take sleeping pills. But what are the effects of these medicines on their cognitive and physical capacities when they set off several hours later to climb the peaks – an activity which requires optimal alertness and physical fitness? By studying the sleep of 24 volunteers at high altitude from July to October 2016, the experiment conducted by the Hypoxia Physiopathology laboratory in Grenoble and led by Samuel Vergès, Inserm researcher, and Pierre Bouzat, physician at the University Hospital of Grenoble, attempts to provide some responses.
Find the report in issue 33 of Science&Santé magazine (in French)