Used Book in Good Condition</br></br>Product Description</br></br><div> <span>Marathons have become too easy for some runners. What was once the pinnacle of achievement in a runner's life is now a stepping stone for extraordinary adventure in ultramarathoning. The number of ultrarunners--those running distances of 50k (31 miles)?? 50 miles?? 100k (62 miles)?? or 100 miles--is growing astronomically each year.</span><br> <span>?</span><br> <span>Dean Karnazes' <i><span>Ultramarathon Man </span></i>and Chris McDougall's <i><span>Born to Run </span></i>have inspired " of thousands to try these seemingly superhuman distances. But to date?? there h