The first family of taekwondo is alive and kicking. Steven, 33, and Diana Lopez, 27, will be back at another Olympics after winning their weight classes at the U.S. trials in Colorado Springs on March 10-11. While that's a superb feat for a pair of such talented siblings, the result was actually bittersweet; their brother Mark Lopez, 29, lost in the finals to Terrence Jennings, ending what would have been a bid to match the history they made four years ago.

At the Beijing Games, the three Lopezes each won medals -- silver for Mark and bronzes for Steven and Diana. It marked the first time three siblings competed at the same Olympics for the United States since 1904 and the first time three won medals at the same Olympics. The three siblings each won gold medals at the world championships in Madrid in 2005.

Diana defeated Danielle Holmquist, 3-1, in her final match to advance to her second Olympics, despite battling injuries on her road to London.

Having worked his way through the challengers' bracket in Colorado Springs, Mark needed to beat Jennings twice to earn another Olympic berth. He lost in the second match and will instead go back as Steven's training partner.

Now, Steven has reached his own rarefied place in the sport. He won gold medals at the Games in Sydney and Athens and he has five golds at world championships, between 2001 and 2009. "I'm in a constant state of refinement," he says. "You always want the perfect performance. You do get sore and it's hard to give up things in other parts of your life, but it's an opportunity of a lifetime."

Having Mark on the sidelines will be bittersweet for Steven, but the Olympic effort will be a family affair, as always. Oldest brother Jean, also a former world medalist, has coached the younger three throughout their Olympic journey. The bronze in Beijing is still an unpleasant reminder. "After the previous two Olympics and five world championships things have become almost automatic," he says. Almost business as usual where I was going to go out and win the gold medal. It didn't work out that way. I feel I can still improve. In the grand scope of things you don't have that many opportunities to be in the best shape of your life."

Kim Rhode has won a medal in the last four Olympics, and could be the first U.S. athlete to win a medal at five Games.

USA Shooting/Reuters

But as impressive as Steven Lopez' longevity is, consider the staying power of Kim Rhode, an Olympic shooter who is talking about competing for another four or five Olympics after making her fifth appearance in London. "I don't see stopping anytime soon," She says.

Why should she? At 32, Rhode could become the first U.S. athlete in any sport to win a medal at five Olympics. She won gold medals in the double trap event in 1996 and 2004, a bronze in double trap in 2000 and a silver in 2008 in the skeet event for which she has qualified again. Rhode became the first athlete to qualify for the 2012 Games when she earned the berth last year, and she is ranked no. 1 internationally. "No pressure, right," she said from Arizona, where she is preparing for a World Cup in trap shooting.

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