I did not enjoy my run yesterday. It was my long run of the week, and it was intensely humid, even early in the morning. I felt tired before I got off the front porch. Every mile was hard work; some might have even qualified as grueling. Along the way, aches and pains that have not cropped up for months returned, en masse it seemed, to remind me over the course of two hours, of every single running injury I've ever sustained. And at least once or twice during the run, that old question resurfaced: "Why am I doing this?"

My current best answer to this question occurred to me while reading Maria Coffey's Explorers of the Infinite. The book focuses on the spiritual and paranormal experiences of extreme athletes, including mountaineers, cyclists, ultra-marathoners, and the like. And while I don't presume to lump my quite moderate addiction to distance running in with their experiences, there's common ground and language, enough to make the stories both compelling and somehow useful in understanding my own compulsions.

Coffey documents these experiences in terms of the causes (fear, extreme focus, suffering) and the experiences themselves (intense connection, precognition, other types of extra sensory perception, ghosts). This matrix of spiritual and extreme physical that underlies the book touches on a number of religious traditions and world-views and illuminates common experiences. Coffey also presents skeptical, scientific explanations (many of which seem like the most likely explanations) for a number of the seemingly paranormal experiences.

The answer to "why am I doing this," is related in a number of ways to the answer to a deeper "why" - the core "why" that drives all religion and philosophy. And as a Catholic who practices the tradition of fasting during Lent, for example, I've long accepted that physical deprivation could lead to spiritual re-awakening and reconnection with God - one of many examples of the tangible intersection of the physical and spiritual in my own religion, and one that can be found in many others as well.

In her chapter on suffering, Coffey quotes climber Joe Tasker, who wrote of an expedition up Kanchenjunga in 1978: "I could not answer my own questions of whether I was here because I really wanted to be here or whether I felt I had to drive myself on, no matter the suffering involved...I wondered if climbing one of the world's highest mountains made one a better person, if it would give me courage and strength in other aspects of life. Only reaching the top would answer that and I no longer knew what the motivation was which would enable me to put one foot in front of the other when there was only pain, and shortage of air, and no fun or enjoyment."