IF YOU THINK REINHOLD Messner's yeti sightings were nutty, wait till you hear the tales Maria Coffey turns up in her new book, Explorers of the Infinite (Tarcher/Penguin, $27). The veteran adventurer and author of 2003's Where the Mountain Casts Its Shadow had a couple of extrasensory experiences after her boyfriend died on Everest and she nearly drowned in Morocco, which got her wondering: Why do certain athletes—climbers, snowboarders, singlehanded sailors, and other hard-driving types—seem to have more spiritual and supernatural epiphanies than your regular Joe 10K? Thin air, mental exhaustion, and dehydration might be part of it. But Coffey posits a more curious theory: that athletes' ability to push "beyond human consciousness into another realm" helps them break physical boundaries, and vice versa. Here are a few of the mind-boggling tales in her case files:

In 1985, after Mexican climber Carlos Carsolio attempted Nanga Parbat's Rupal Face with a Polish team, tapes of their dicey descent revealed that Carsolio had spoken in Spanish while the other climbers spoke Polish. " 'But when we were up there we had understood each other perfectly,' " Carsolio said.

While climbing in the Dolomites, British mountaineer Adrian Burgess says, he once watched a basketball-size rock crash directly toward his brother Alan's head—then stop in midair before floating to the right and landing gently on Alan's daypack.

In 1992, a few weeks after Polish climber Wanda Rutkiewicz died in the Himalayas, her mother got a late-night phone call. "She heard her daughter's voice," Coffey writes. "'I am very cold,' the voice said. 'But don't cry, everything will be fine. I cannot come back now.' Then the line went dead."