He's the face of the Games and already has six gold medals -- so could Usain Bolt do the "Triple-Triple" in Rio? Few would bet against the most successful sprint star in Olympic history as he goes in the 100 meters, 200m, and 4x100m relay. He is also aiming to become the first man to win three successive 100m Olympic titles.
He's the face of the Games and already has six gold medals -- so could Usain Bolt do the "Triple-Triple" in Rio? Few would bet against the most successful sprint star in Olympic history as he goes in the 100 meters, 200m, and 4x100m relay. He is also aiming to become the first man to win three successive 100m Olympic titles.
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He's the reigning Olympic champion who simply does not know how to lose -- and Ashton Eaton is looking good for a repeat of his London heroics of four years ago. The world's leader in decathlon, who holds the world record, will be one of the leading medal hopes for the U.S. in Brazil.
He's the reigning Olympic champion who simply does not know how to lose -- and Ashton Eaton is looking good for a repeat of his London heroics of four years ago. The world's leader in decathlon, who holds the world record, will be one of the leading medal hopes for the U.S. in Brazil.
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Genzebe Dibaba was named as the Laureus female athlete of the year in 2015 after breaking three world records in two weeks, setting new marks in the 1,500m indoor, 3,000m and two mile indoor events. The Ethiopian, 25, will be going for gold in the 1,500m.
Genzebe Dibaba was named as the Laureus female athlete of the year in 2015 after breaking three world records in two weeks, setting new marks in the 1,500m indoor, 3,000m and two mile indoor events. The Ethiopian, 25, will be going for gold in the 1,500m.
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Dutch sprinter Dafne Schippers will be aiming for double gold in Rio with the 100m and 200m on her radar. Schippers, who clocked a world record time to win the 200m at the 2015 world championships, won silver in the shorter distance.
Dutch sprinter Dafne Schippers will be aiming for double gold in Rio with the 100m and 200m on her radar. Schippers, who clocked a world record time to win the 200m at the 2015 world championships, won silver in the shorter distance.
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<a href="index.php?page=&url=http%3A%2F%2Fedition.cnn.com%2F2016%2F07%2F18%2Fsport%2Frio-2016-usain-bolt-fraser-pryce%2F">Shelly-Ann Fraser-Pryce </a>is aiming to become the first athlete to win three straight 100m golds at the Olympics -- and she could do it before Usain Bolt. This time around she's dropped the 200m and will be putting all her focus and energy into the 100m. Her opponents have been warned.
Shelly-Ann Fraser-Pryce is aiming to become the first athlete to win three straight 100m golds at the Olympics -- and she could do it before Usain Bolt. This time around she's dropped the 200m and will be putting all her focus and energy into the 100m. Her opponents have been warned.
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She was the face of the London 2012 Games and one of the big winners on a historic "Super Saturday" -- but there could be even more success to come for Jessica Ennis-Hill. The Olympic and world heptathlon champion, is in great shape going into Rio and is one of the favorites for gold.
She was the face of the London 2012 Games and one of the big winners on a historic "Super Saturday" -- but there could be even more success to come for Jessica Ennis-Hill. The Olympic and world heptathlon champion, is in great shape going into Rio and is one of the favorites for gold.
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South Africa's Caster Semanya is one of the big names chasing success in the 800m in Rio. Semenya has been in fine form this year and could even double up in the 400m. She was forced to undergo gender testing after becoming the world 800m champion in 2009 before going on to win silver in t<a href="index.php?page=&url=http%3A%2F%2Fedition.cnn.com%2F2012%2F08%2F08%2Fworld%2Feurope%2Folympics-semenya-debut%2F">he event at the London 2012</a> Olympics.
South Africa's Caster Semanya is one of the big names chasing success in the 800m in Rio. Semenya has been in fine form this year and could even double up in the 400m. She was forced to undergo gender testing after becoming the world 800m champion in 2009 before going on to win silver in the event at the London 2012 Olympics.
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<a href="index.php?page=&url=http%3A%2F%2Fedition.cnn.com%2F2016%2F07%2F06%2Fsport%2Fkatie-ledecky-rio-2016-us-swimming%2F">Katie Ledecky stunned the world at London 2012 </a>by clocking the second fastest 800m time in history and winning the gold at the age of just 15. Since then, the U.S. star has set 11 world records and won every major international race she has competed in.
Katie Ledecky stunned the world at London 2012 by clocking the second fastest 800m time in history and winning the gold at the age of just 15. Since then, the U.S. star has set 11 world records and won every major international race she has competed in.
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Having won four gold medals and a bronze in London, Missy Franklin will be leading the charge for Team USA in the pool once again. Now 21, and the holder of six world championship gold medals, she'll be the one to beat rather than the surprise package as she was four years ago.
Having won four gold medals and a bronze in London, Missy Franklin will be leading the charge for Team USA in the pool once again. Now 21, and the holder of six world championship gold medals, she'll be the one to beat rather than the surprise package as she was four years ago.
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Michael Phelps will compete at a fifth Olympic Games with an eye on adding to his haul off 22 medals -- 18 of which are gold. The 31-year-old retired from the pool after the 2012 Games but made his comeback two years later.<br />
Michael Phelps will compete at a fifth Olympic Games with an eye on adding to his haul off 22 medals -- 18 of which are gold. The 31-year-old retired from the pool after the 2012 Games but made his comeback two years later.
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Golf makes its return to the Games after a 112-year absence and Lydia Ko is hoping to play a starring role. At 19, the Korean-born New Zealander is already the world No.1 and is hoping to add a gold medal to her already extensive trophy haul.
Golf makes its return to the Games after a 112-year absence and Lydia Ko is hoping to play a starring role. At 19, the Korean-born New Zealander is already the world No.1 and is hoping to add a gold medal to her already extensive trophy haul.
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Two years ago the tears flowed as Brazil's World Cup adventure came to a shuddering halt. Now Neymar is hoping to bring a smile back to his homeland with success in the football tournament. He skipped the Copa America to play at his home Games and the Barcelona star will be the main man in Rio.
Two years ago the tears flowed as Brazil's World Cup adventure came to a shuddering halt. Now Neymar is hoping to bring a smile back to his homeland with success in the football tournament. He skipped the Copa America to play at his home Games and the Barcelona star will be the main man in Rio.
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Uzbekistan's Oksana Chusovitina will be competing at her seventh Olympics -- a record which no other gymnast can match. Her first Games was back in 1992 where she won a gold medal there as a member of the Unified Team (made up of athletes from former Soviet countries). She won bronze for Uzbekistan on the vault at Beijing in 2008 and will be hoping for more success this time around at the age of 40.
Uzbekistan's Oksana Chusovitina will be competing at her seventh Olympics -- a record which no other gymnast can match. Her first Games was back in 1992 where she won a gold medal there as a member of the Unified Team (made up of athletes from former Soviet countries). She won bronze for Uzbekistan on the vault at Beijing in 2008 and will be hoping for more success this time around at the age of 40.
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Japan's<a href="index.php?page=&url=http%3A%2F%2Fedition.cnn.com%2F2015%2F10%2F21%2Fsport%2Fkohei-uchimura-gymnastics-olympics-japan%2F"> Kohei Uchimura is aiming to defend his all-around title</a> at Rio after his success in London. With the next Olympics in his home country of Japan, the 27-year-old is hoping to head into Tokyo as a double Olympic champion.<br />
Japan's Kohei Uchimura is aiming to defend his all-around title at Rio after his success in London. With the next Olympics in his home country of Japan, the 27-year-old is hoping to head into Tokyo as a double Olympic champion.
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She's only 19 but Simone Biles is already the most decorated American female gymnast in World Championships history with a total of 14 medals -- including a record 10 golds. She's the first woman in 42 years to win four straight national title and the first African-American to be world all-around champion and first woman to win three consecutive world all-around titles.
She's only 19 but Simone Biles is already the most decorated American female gymnast in World Championships history with a total of 14 medals -- including a record 10 golds. She's the first woman in 42 years to win four straight national title and the first African-American to be world all-around champion and first woman to win three consecutive world all-around titles.
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New Zealand's Lisa Carrington has ruled the waves in the canoe world since winning gold in the K-1 200m at the 2012 Games -- just a year after she had become world champion. The 27-year-old is going for gold in both the K1 200m and K1 500m and is unbeaten in the shorter distance over the past five years. She won her fourth consecutive world title over the K1 200m distance last year, after securing the K1 500m world championship crown for the first time.
New Zealand's Lisa Carrington has ruled the waves in the canoe world since winning gold in the K-1 200m at the 2012 Games -- just a year after she had become world champion. The 27-year-old is going for gold in both the K1 200m and K1 500m and is unbeaten in the shorter distance over the past five years. She won her fourth consecutive world title over the K1 200m distance last year, after securing the K1 500m world championship crown for the first time.
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Kim Woojin of South Korea has already won two world championship titles but this will be the archer's first Olympics. The 24-year-old missed the cut in 2012 but will be one of the favorites this time around.
Kim Woojin of South Korea has already won two world championship titles but this will be the archer's first Olympics. The 24-year-old missed the cut in 2012 but will be one of the favorites this time around.
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Italy's Rossella Fiamingo will be looking to add the Olympic épée title to her two world championship crowns. The 25-year-old, who hails from Catania, is her country's big hope for gold in Rio.
Italy's Rossella Fiamingo will be looking to add the Olympic épée title to her two world championship crowns. The 25-year-old, who hails from Catania, is her country's big hope for gold in Rio.
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Brazil's beach volleyball duo Talita Antunes and Larissa Franca are big favorites to win gold in their home Games. The pair are seeded No.1 in the draw and were winners the 2015 FIVB Beach Volleyball World Tour.
Brazil's beach volleyball duo Talita Antunes and Larissa Franca are big favorites to win gold in their home Games. The pair are seeded No.1 in the draw and were winners the 2015 FIVB Beach Volleyball World Tour.
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Britain's Nicola Adams will arrive in Rio as the reigning Olympic, world, Commonwealth and European Games champion. The 33-year-old flyweight is aiming to become first British boxer since Harry Mallin in 1924 to successfully defend an Olympic gold medal.
Britain's Nicola Adams will arrive in Rio as the reigning Olympic, world, Commonwealth and European Games champion. The 33-year-old flyweight is aiming to become first British boxer since Harry Mallin in 1924 to successfully defend an Olympic gold medal.
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