A day before a mixed martial arts fight, competitors determined to gain a competitive edge and fight at a lower weight class often dangerously dehydrate themselves, sometimes dropping close to 20 percent of their weight in a matter of hours. Correspondent David Scott examines the serious health complications associated with weight-cutting, which has endangered fighters' lives, and at times, proven to be fatal, leaving some in the sport to question whether the age-old practice should be reined in.