News Women's boxing made a hugely successful Olympic debut at the London 2012 Games and the world's top female warriors are now preparing to go into battle for medals again at the Rio 2016 Games   With 45 days until the opening ceremony, Rio2016 com profiles three of the leading women practitioners of the 'sweet science' Claressa Shields She calls herself ‘T-Rex’ on Twitter and Shields aims to roar into the history books in Rio Already one of the most decorated US amateur boxers, she defended her middleweight world title by defeating her Dutch opponent Nouchka Fontijn in Kazakhstan last month, and next up is her defence of the Olympic medal she won, aged 17, in London “If I could tell something to my 17-year-old self, I would tell her good things come to those who wait,” Claressa told ESPN when thinking back to London 2012 “God didn't bring you this far to turn around on you ” Shields, an inspiration for young girls around the world, has good chance of becoming the first American boxer to earn gold at multiple Olympic Games The 21-year-old from from Flint, Michigan has only lost one fight, back in May 2012 at the world championships against british boxer Savannah Marshall   Katie Taylor The pride of Ireland, the five-time world champion and winner of six European championship gold medals is widely regarded as the best woman boxer of all time In Rio, she will be out to defend the Olympic lightweight title she won at London 2012 “Gold in Rio would be my greatest achievement,” she told The Irish Times Taylor started boxing at age 11; she was coached by her father and trained with her older brothers Lee and Peter At 15, she fought the first officially-sanctioned female boxing match in Ireland and defeated Alanna Audley from Belfast The boxer recently lost her first world championship bout in 11 years, beaten by France’s Estelle Mossely, who she will face again soon “I have another chance thankfully in the Olympic Games, so we will see how that goes,” she said   Nicola Adams When Adams floored Chinese boxing great Cancan Ren to become flyweight champion at London 2012, she wrote herself into the history books as the first woman to win an Olympic boxing gold medal She went on to become a household name in Great Britain, even pursuing a television career Now her focus on fully back on defending her title in Brazil “I want to be the first (female) Brit to win two Olympic golds in boxing, so I’ll do everything it’ll take,” she told The Guardian last week Adams trains three times a day for at least two hours Adams is from Leeds, England, and started boxing aged 12 at an after-school programme she had to attend when her mother couldn't get a babysitter She has also played other sports like golf, archery, shooting and quad bike riding Last month, the reigning Olympic, Commonwealth and European Games champion completed her gold medal collection after defeating Thailand’s Peamwilai Laopeam in the flyweight final at the world championships in Kazakhstan When she is not throwing punches, she loves spending time with her friends, her family and her dobermann dog, Dexter She admires her mum as much as she admires Muhammad Ali or Sugar Ray Leonard More on boxing Tributes pour in for Muhammad Ali, the boxing legend who transcended sport Boxing venue for Rio 2016 Olympic Games unveiled Boxers from 19 countries to take part in Rio 2016 Olympic test event at Riocentro