Ms. Cuthbert waves as she and three-time silver medalist Raelene Boyle carry the Olympic torch at the 2000 Sydney Olympics. (David Guttenfelder/AP)

Betty Cuthbert, an Australian sprinter who was a standout at the 1956 Melbourne Olympics with her sweep of three gold medals, and who drew even greater admiration from her countrymen later in life, when multiple sclerosis had robbed her of the ability to run, died Aug. 6 in Perth, Australia. She was 79.

Her death was announced by the International Association of Athletics Federations (IAAF) and the Australian Olympic Committee.

Ms. Cuthbert was diagnosed with her degenerative neurological disease in 1969, five years after she claimed her fourth and final gold medal at the 1964 Tokyo Games. She also suffered a brain hemorrhage in 2002. Two years earlier, she had made a memorable appearance at the 2000 Summer Games in Sydney, bearing the Olympic flame as a fellow athlete pushed her in a wheelchair.

Known to Australians as their “Golden Girl,” Ms. Cuthbert was celebrated as one of the greatest track and field athletes of her era. She also earned a reputation as one of the most unassuming: Not expecting to participate in the 1956 Games as a competitor, she had bought passes to attend as a spectator.

She was 18 years old at the time and had prepared for the Olympics by squeezing in training sessions when she was not working at her family’s plant nursery. Her athletic talent was obvious, however, and she found an early mentor in Australian silver medalist June Maston Ferguson.

Ms. Cuthbert crosses the finish line to win the women's 400-meter race at the 1964 Tokyo Olympics. (AP)

At the 1956 Games, Ms. Cuthbert won gold medals in the 100- and 200-meter sprints and in the 4x100 relay with teammates Shirley Strickland de la Hunty, Norma Croker and Fleur Mellor. Ms. Cuthbert cut an unusual profile, propelling herself around the track with her mouth gaping open.

“The heroine of the main stadium, the athlete who became known as Australia’s Golden Girl, was a tearaway sprinter called Betty Cuthbert,” the Australian Olympic Committee quoted historian Harry Gordon as saying. “She had straw-colored hair and a distinctive, wide-mouthed manner of gulping air that made her look to be roaring exultantly as she streaked down the track.”

(Ms. Cuthbert later recalled that her mouth hurt as she ran, but that she admonished herself, “You can’t stop to shut it now.”)

All of a sudden, with her triple gold, she was a global teen celebrity. She dined with Queen ­Elizabeth II and Prince Philip of ­England.

Australians pinned their hopes on Ms. Cuthbert for the 1960 Olympics in Rome, but a hamstring injury prevented her from competing. She said she considered herself retired and returned to the family business until she began hearing what she believed to be the voice of God.

“Run again,” it told her, insistently, over months. “It got so bad at night I couldn’t sleep,” she told the Sydney Morning Herald in 1997. “In the end, I said, ‘Okay, you win, I will run again.’ ”

She rebounded to compete in the Tokyo Games, winning gold in the 400-meter race. “It wasn’t me running really that day,” she told an interviewer for the organization Athletics Australia, professing that God had picked up her feet, and she had put them down on the track.

Her multiple sclerosis came upon her slowly at first, causing tingling sensations in her muscles and blurred vision. For years she relied on a wheelchair for mobility. In recent years, according to reports in the Australian media, a con artist defrauded her and a caregiver of their life ­savings.

Elizabeth Cuthbert was born in New South Wales on April 20, 1938. “When I was growing up,” she recalled, “I just liked running. I would run everywhere,” including up and down the rows of her father’s plants.

She attracted national attention shortly before the 1956 Games, when, at a pre-Olympic competition, she set a world record for the 200-meter race, according to Athletics Australia. The performance made her spectator’s ticket obsolete.

A bronze statue of Ms. Cuthbert — mid-stride, with her mouth wide open — stands outside the Melbourne Cricket Ground, and she was an honoree of the IAAF Hall of Fame. At the induction ceremony, she experienced what she said was the ultimate glory of her career, when she received a compliment from Usain Bolt, the Jamaican runner who today reigns as the fastest man in the world. “You sure could run,” he said.

Ms. Cuthbert did not marry or have children. A compete list of her survivors was not immediately available.

Beyond her athletic honors, she was widely recognized for her fundraising and other work on behalf of people suffering from multiple sclerosis.

“God gave it to me for a reason — that’s all I used to think. I never, ever, once said, ‘Why me?’ ” she told the Morning Herald. “God wanted me to use this to help other people.”