Retton began studying dance and acrobatics at age four, starting gymnastics training a year later. In 1983 she moved to Houston, Texas, to train with Bela Karolyi, who helped Retton develop a style that suited her compact, muscular frame. In contrast to the fluttering, balletic movements then popular in floor-event performance, Retton's revolutionary style exhibited speed, accuracy, and power and transformed women's gymnastics.

Retton was successful at major American and international tournaments during the early 1980s, becoming the first American to win the combined-events title at the Chunichi Cup in Japan (1983). At the 1984 U.S. national championships, she won first place in the vault, floor exercise, and all-around events. Later that year she made her Olympic debut.

In the all-around competition, Retton trailed the Romanian team's Ecaterina Szabo by 0.05 points going into the final rotation and needed a perfect score of 10 on the vault to win the gold. She executed the exceptionally difficult Tsukahara vault—a twisting layout back somersault—flawlessly, winning the gold. In addition, she led the U.S. women's team to a silver, its first medal since 1948, and won individual medals in the vault (silver), the uneven parallel bars (bronze), and the floor exercise (bronze).

Soon after the Los Angeles Games, Retton retired from competition and became a motivational speaker and a television commentator. In 1985 she became the first gymnast to be inducted into the U.S. Olympic Hall of Fame.