His 100-meter time (10.35 seconds) marked the fastest ever in an Olympic decathlon.
In the Olympic cycling trials in April, she finished second to Tammy Thomas in the 500-meter time trial.
She will race in the 500-meter time trial, where she placed fourth in the 1998 world championships.
In 2011, he managed to knock two seconds off his 100-meter time from the previous year.
Liu holds the second fastest 110-meter time ever (12.88) and the second best time in the world this year 12.977, behind the 12.93 run by Merritt).
MEXICAN WOMAN WINS TIME TRIAL: Nancy Contreras of Mexico won the women's 500-meter time trial title yesterday at the world track cycling championships in Antwerp, Belgium.
Rupp, 17, represented the United States at the world youth championships last month in Sherbrooke, Quebec, where he lowered his best 3,000-meter time to 8 10.42.
Felicia Ballanger of France, the world record-holder at 34.0 seconds in the 500-meter time trial, will be favored in Sydney.
She won a bronze medal at the 1992 world junior championships and followed with national championships in the 500-meter time trial in 1996 and '98.
Witty won the 1998 national championship and finished fourth at the 1998 world championships in the 500-meter time trial, a two-lap race against the clock.
