Bone games
"Extreme physical effort, especially when coupled with risk and deprivation, has been known to produce preternatural effects in people. These range from 'runner's high', or being 'in the zone', to far more mystical experiences - visions, hallucinations, and superhuman performance. [This] is the story of Rob Schultheis's exploration of this strange terrain - the altered states of consciousness, or access to something that is unknown, that is the elusive product of extreme sports, going beyond the easy parameters of normal life ... He finds the paranormal in rock-climbing, mountaineering, ultrarunning, kayaking, climbing and hang-gliding ... in accounts of Arctic explorers and shipwreck victims. He finds parallels in shamanistic practices and Zen buddhism"--Publisher's description.