Five years ago, Dr. Konrad E. Bloch, of the University Hospital of Zurich, Switzerland, was 50 and had only limited climbing experience, but he wanted to study high altitude related illnesses. So Bloch and his colleagues recruited 35 healthy climbers for a trip that was half adventure travel, half clinical trial. In July 2005, the group flew to Islamabad and then took a five-day bus trip to China’s Mount Muztagh Ata (about 24,757 feet or 7,546 meters high).
The climbers were split into two groups and told to climb the mountain at different speeds. On some nights, the climbers wore high-tech shirts equipped with sensors that measured their breathing and heart patterns, along with their blood oxygen levels. About half the climbers never made it to the top of the mountain, turning back because of altitude sickness, exhaustion, and in one case, traveler’s diarrhea.
The hearty mountaineers appear in photos to be in pretty good spirits and not to mind being test subjects:
[Images: Swiss Research Expedition]