She was inspired to enter Starfleet due to the disappearances of her grandfather and the rest of the crew of the USS Coronado. In 2254, she began taking performance enhancing genetic procedures from an unscrupulous doctor in San Francisco, Schaeffer. She increased her strength and stamina to levels greater than normal humans.
She had survived several deadly falls, including one from the Golden Gate Bridge in 2255 in which she saved James T. Kirk. She and Kirk split when Schaeffer was arrested late in the school year. (TOS - Starfleet Academy novel: The Edge)