At a little over 5 feet, 7 inches, freshman Julia Ratcliffe is far from being the biggest weight thrower. But she is strong.

In her first competition as a Tiger at Princeton’s New Year’s Invite on Dec. 9, Ratcliffe repeatedly crushed the Ivy League record as she unleashed soaring throw after throw. Accelerating through a four-turn spin, Ratcliffe whipped the 20-pound ball and chain around her head and hurled it 19.23 meters on her second attempt — erasing the old conference record of 19.21 set in 2010 by Princeton’s Thanithia Billings ’11. By her fifth attempt, Ratcliffe had pushed the record a foot farther, throwing 19.58 meters...