Griffith-Joyner, who became better known as `Flo-Jo', first came to world attention during the US trials for the South Korean Olympics, which included a world record 10.49 seconds in the 100 metres. She went on to show scintillating form in the Games, where she won the 100m in a wind-assisted 10.54sec, then set two world records at the 200m, 21.56sec in the semi-final and 21.34sec in the final.
Griffith-Joyner was almost as well known for her appearance - her lurid self-designed running costumes and trademark six-inch fingernails - as her performances, but her career was not without controversy. She retired immediately after the 1988 Games, with many critics claiming her meteoric rise to prominence had been achieved with the aid of performance-enhancing substances. A muscular physique prompted talk of steroid use but the athlete always denied such accusations and she never tested positive in drugs tests. She had health problems, however, as a heart seizure in 1996 - from which she had apparently recovered - demonstrated.
Johnson, who won the 100m in Seoul in a world record 9.79sec and was then stripped of his medal and banned for two years after testing positive for steroids, had his appeal against a lifetime ban rejected. The ban was imposed in 1993, when Johnson tested positive a second time for using steroids. His manager had said the sprinter would try to take his case to Canada's Supreme Court if he lost yesterday's appeal.