this week's series "extreme living." he beginning withen ultramarathoner. one who tackles races of more than 150 miles a pop and one of the fastest runners in race history. in a moment, sanjay goes one-on-one. but first, we go up close with the racer and athlete defying all odds. >> scott has been called "the king of pain." and the greatest ultramarathoner ever. ultramarathons can be 125 miles longer than a typical 26-mile marathon. scott finished his first in 1994 and since then, he's dominated the sport. today he holds records for races that cover more than 150 miles and last over 24 hours straight. a notoriously tough ultramarathon is the 135-mile bad water in death valley, california. the 2005, to debt true the 135 degree heat, scott was dunked in this king sized cooler full of ice water.