Sport: The Swim Twins

"Ladies, take your marks!" The starter's gun barked, and six of the U.S.'s fastest women swimmers slammed into the water of Chicago's Portage Park pool, arms flailing and legs churning. On the fourth lap, the freckle-faced blonde in Lane 4 began to pull away—increasing her lead with each powerful stroke, while her competitors strained vainly to match her pace. At the finish of the 1,500-meter freestyle, Carolyn House was a full 30 meters ahead. Her time: 18 min. 44 sec.—smashing the world record by 18.8 sec. During the next three days at the...