Now, the pair have their eyes on Rio, and are working with some of the best track and field competitors to help them also achieve gold.
Joyner-Kersee, 54, who won three gold, one silver and two bronze medals in the women’s heptathlon and the women’s long jump at four different Olympic Games, says her relationship with current athletes is that of mentor.
“I just like sending things because I know how our sport can be at times and sometimes that can be a love-hate type of relationship. You’re doing well, everybody embraces you, and all of a sudden you fall off and you’re wondering where those people are,” she tells PEOPLE. “I’m always one to say, ‘Hang tough, hang in there.’ ”
O’Brien, 49, who won gold for the men’s decathlon in 1996, will be in Rio this summer and says that more than anything, they’re cheerleaders for these young athletes.
“We really provide a lot of encouragement,” he says. “I speak with Ashton Eaton and his coach on a regular basis. His coach sends me texts: ‘Ashton jumped 18 feet and I’m in the pole vault in practice.’ In the decathlon community, we keep track of everybody.”
As this summer’s Olympics approach, Joyner-Kersee is working with athletes Dawn Harper and Allyson Felix, whom Joyner-Kersee predicts could win gold at this year’s Games.
“I’m real biased toward the American athletes, and this is extremely tough because we haven’t had our Olympic trials yet, and I’m very hopeful that Allyson Felix will be one,” Joyner-Kersee says.
On the men’s side, O’Brien predicts Eaton, who won the gold medal in the decathlon in London, will be on the medal stand again. If he wins back-to-back gold, he’ll become only the third man in history to do so.
“If I was a betting man, I’d bet my house on it,” says a confident O’Brien. “In my opinion, he has to get injured for him to lose. He’s that much better than the rest of the field.”
Although Team USA looks strong on the track, Joyner-Kersee and O’Brien say other countries to look out for include the Bahamas, Trinidad, Great Britain and China.
Another one to watch is Pau Tonnesen, a decathlete whom O’Brien coached at the World Championships. Although Tonnesen attends the University of Arizona, he will be competing for Spain.
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For all the competitors, Joyner-Kersee and O’Brien agree that half the battle is mental – something they learned during their own paths to Olympic victory.
“For 20 seconds, I’m going to forget that I’m married, I’m going to forget that I have kids, forget about the troubles in the world, and run the turn and the high jump and convert it to vertical take off – and that’s focus,” O’Brien says. “Nothing in the world matters.”
To learn more about all Olympic hopefuls, visit teamusa.org. The Rio Olympics begin Aug. 5.