Kilian Jornet was profiled a few days ago by the New York Times in this article: Creating the All Terrain Human. Read his incredible accomplishments, and marvel at his age. The term "super-human" comes to mind. And grounded and humble as well, evidenced by this National Geographic interview from Sept 2010.
Looking at Chasqui runners of the ancient Inca Empire, and today's East African runners, it appears the 'naturally gifted' endurance athletes have the common denominator of enlarged lung capacity, due to a lifetime in the mountains. Those of us sea-level dwellers will never have that advantage. But these 'super-human' athletes will tell you - they weren't born fast or born able to cover long distances. It came with year after year of hard work. And it came with an understanding of his training environment. Jornet is not motivated by shattering more and more world records, but by a deep passion for nature, an appreciation and respect of the beauty around him, and wanting to connect with it.
I've been slacking on longer distances lately. But, a local trail running group starts up in a few weeks. I'll be there. I may not be 'part-mountain goat', but I do find inspiration, traquility, and even a tiny bit of speed when I go off-road. Best of all, I find the desire I have been lacking to go farther.