Jennifer Armstrong was born in New Zealand. She competed for that country in the Europe class at Barcelona 1992, where she finished fourth. In 1997, now living in Australia, Armstrong linked up with fellow Western Australian Belinda Stowell in the 470s and they came under the tutelage of the noted Ukrainian coach Victor Kovalenko, who had recently come to Australia.
Armstrong and Stowell first competed at the 470 world championship in 1998, where they finished twenty-eighth. A ninth placing in 1999 and a second in 2000 put them as medal hopes at Sydney 2000. On Sydney Harbour, in The Ugly Duckling, they won the gold medal, from the American and Ukraine crews, and became the first Australian women to win a sailing medal at the Olympic Games.
On the same day in Sydney, Tom King and Mark Turnbull won the gold medal in the men’s 470s. Twenty-eight years earlier, at Munich 1972, John Cuneo, John Shaw and Tom Anderson won the Dragon class and David Forbes and John Anderson won the Star class on the same day. At Beijing 2008, Malcolm Page and Nathan Wilmot and Tessa Parkinson and Elise Rechichi won gold medals in men’s and women’s 470s respectively, on the same day.
Armstrong and Stowell pressed on to Athens 2004 in the hope of winning back-to-back Olympic titles, but they finished fourteenth. Soon after Athens, Armstrong retired from international sailing.