By Peggy Shinn | Aug. 20, 2015, 12:47 a.m. (ET)
Michael Phelps after competing in the men's 200-meter breaststroke final during the 2015 Phillips 66 National Championships at the Northside Swim Center on Aug. 10, 2015 in San Antonio.


At the London 2012 Olympic Games, 127 different Team USA athletes won gold medals — and 10 U.S. Olympians earned more than one.

Leading the charge were Michael Phelps and Missy Franklin, who collected four gold medals each. Phelps is on track to add to his 22-medal collection in Rio after swimming the fastest time of the year in the 100-meter butterfly, 200-meter butterfly and 200-meter individual medley.

And although Franklin struggled at the 2015 world championships, missing a medal in the 100-meter backstroke — one of her signature events — and finishing second in the 200 backstroke and third in the 200 freestyle, she will be a multi-medal favorite in her second Olympic Games.

But in Rio, Katie Ledecky — breakout winner of the 800-meter freestyle in London when she was 15 years old — is the leading candidate to win multiple gold medals. She has won nine world championship titles and perhaps more importantly, Ledecky, now 18, has won every international race that she has entered since winning gold in London. She has also set world records in so many races that it’s difficult to keep count. And she just keeps breaking them. Most recently, she broke her record in the 800 and 1,500 free at the 2015 worlds.

In Rio, Ledecky could win five or more gold medals. After her performance at the 2015 worlds, she will likely be a threat in the 200, 400 and 800 freestyles, plus relays. And few will be surprised if she also qualifies in the 100 free.

Other multiple gold medalists in Rio could be Ryan Lochte, 31, and Nathan Adrian, 26. Although Lochte finished just off the podium in the 200 free at the 2015 world championships, he swam the fastest time in the semifinals and rebounded to win the 200 individual medley for his fourth consecutive title in the event.

Adrian is leading the charge for the U.S. men in both the 50- and 100-meter freestyle events. In addition to defending his Olympic golds in the 100 free and 4x100 medley, his goal is to also compete in the 50 free, as well as the 4x100 free, in Rio.

Lochte and Adrian will be key swimmers as the U.S. men try to recapture gold in the 4x100 freestyle. Team USA once dominated this relay but took silver at the London Games, then failed to make the final at this year’s world championships.

Six-time Olympic medalist Matt Grevers, 30, who took it easy during 2013 and got married, signaled his comeback by winning a bronze medal in the 100 backstroke this week at the 2015 world championships.

Another defending gold medalist looking to make a splash in Rio is diver David Boudia. His gold medal in men’s 10-meter platform diving was the culmination of a dream that began in 1996 when he watched the Opening Ceremony of the Atlanta Olympic Games on TV.

“It’s hard to fathom when a dream is accomplished like being an Olympic champion because you’ve worked so hard through the years,” Boudia said. “It finally happens, you’re kind of in disbelief.”

Since then, he has continued a medal-winning streak at world championships, taking his third consecutive silver medal in 10-meter platform diving at the 2015 FINA World Championships — and fourth silver medal overall (he earned silver in 10-meter synchro at 2009 worlds).

“I definitely know that I’m going back to defend that title (in Rio) in the platform event,” he said.

In track, 200-meter gold medalist Allyson Felix, 29, is focused solely on the 400-meter at the 2015 world championships in Beijing later this month due to the schedule, but could double up and add the 200 for Rio.

If Felix does qualify to compete in the women’s 400 in Rio, she will be vying for the win against defending gold medalist Sanya Richards-Ross.

"I do want to join Marie Jose-Perec as the second woman ever to win back-to-back in the 400m,” Richards-Ross recently told SportingNews.com. “I know it's going to be a tough feat. I know the 400m is a challenge and that women all over the world want to win that medal.”

Still hampered by her right big toe — she has had two surgeries since the London Games — Richards-Ross, 30, finished fifth in the 400 at U.S. nationals (a race won by Felix) and did not qualify for the 2015 world championships. If Richards-Ross qualifies for Rio, it will be her fourth Olympic Games.

After a season competing in the 400-meter hurdles, Ashton Eaton is aiming to defend his world and Olympic decathlon titles in 2015 and 2016.

So why a season of hurdles?

“He likes to run the quarter, he's a good hurdler, it makes sense from the standpoint of training as a 400 hurdler in order to make him better at the 400 meters and the 1,500 meters,” his coach Harry Marra told RunnerSpace.com last season.

In Rio, Eaton is aiming to join American Bob Mathias and Britain’s Daley Thompson as the only decathletes to win more than one Olympic title.

Of USA Gymnastics’ Fierce Five, everyone except Jordyn Wieber has expressed interest in competing for Team USA in 2016. At the 2015 U.S. championships earlier this month, Aly Raisman finished third and Gabby Douglas finished fifth. Kyla Ross, who earned bronze at the 2014 world championships, finished 10th.

McKayla Maroney has not competed since winning the world vault title in 2013. According to women’s national team coordinator Martha Karolyi, Maroney is suffering from “heart problems” and is not regularly training at this time.

After winning her third Olympic gold medal in beach volleyball with Misty May-Treanor, Kerri Walsh Jennings is now paired with April Ross, who won silver in London with Jennifer Kessy.

Walsh Jennings and Ross dominated competition last year. But Walsh Jennings is now on the mend from separating her shoulder twice this season.

Tennis in Rio could showcase sibling teamwork again. The winning-est pair in doubles tennis history, Mike and Bob Bryan plan on competing in men’s doubles and mixed doubles again at the 2016 Olympics. Then the identical twins told Sports Illustrated that they plan to retire.

Women’s singles champion Serena Williams has also expressed a desire to play in Rio, along with sister Venus in doubles. The Williams sisters have won three Olympic doubles titles.

Kim Rhode, five-time Olympic medalist in skeet and trap, is shooting for Olympic history: six Olympic Games, six Olympic medals. She’s already in the record books as the only American to win five medals in individual competition in five consecutive Games.

Jordan Burroughs is considered one of the best wrestlers in the world. The reigning men’s freestyle Olympic champion and two-time world champion at 74 kg., Burroughs came up short at the 2014 world championships, earning the bronze medal instead of gold. He hopes to regain the title when the world championships come to Las Vegas next month. Then he is aiming for gold again in Rio.

In team sports, USA Basketball plans to continue its Olympic dominance. The U.S. men are gold medalists in 14 of the 17 Olympic Games in which they have played. Notably, the U.S. has won five of the last six Olympic titles when NBA players have participated (1992, 1996, 2000, 2008 and 2012).

Members of the 2014-16 U.S. Men’s National Basketball Team roster, from which the 12-man 2016 U.S. Olympic Team will be selected, include veterans and NBA All-Stars Carmelo Anthony and LeBron James. Should they make the 2016 U.S. Olympic Team, Anthony and James have an opportunity to become the first men’s basketball players in U.S. Olympic history to appear at four Olympic Games.

The U.S. women’s basketball team has been even more dominant and looks to capture its sixth straight — and eighth overall — gold medal at the 2016 Games. The U.S. women’s team is currently riding a 41‐game winning streak in Olympic play, dating back to the bronze-medal game in 1992.

The U.S. women’s water polo team has medaled at every Olympic Games since women’s water polo made its debut in 2000. At the London 2012 Games, they finally broke through to win the gold medal. At the 2015 FINA World Championships, they won their first gold in six years.

One of the highlights of the Rio Olympic Games will no doubt be women’s soccer, where the U.S. women’s soccer team will enter the tournament as the defending Olympic and World Cup champions. In Rio, the team aims to win the United States’ fifth consecutive gold medal and sixth overall since women’s soccer made its Olympic debut in 1996.

World Cup leading scorer Carli Lloyd has no plans to retire. But choosing the team will be a challenge. While 23 women were named to the 2015 World Cup roster, only 20 can qualify for the Olympic Games, with 18 on the final roster.

Kayla Harrison became the first American judoka to win Olympic gold in London and she has continued her winning ways since then. Harrison is currently ranked No. 1 in the world.

The U.S. women’s eight rowing team won the last two Olympic gold medals and is favored to win once again in Rio. The U.S. won the 2013 and 2014 world championships, in addition to setting the current world record at a world cup in July 2013.

A freelance writer based in Vermont, Peggy Shinn has covered three Olympic Games. She has contributed to TeamUSA.org since its inception in 2008.