The most powerful and physically demanding stroke, the butterfly involves simultaneous overhead stroking of the arms combined with a dolphin kick. The dolphin kick features both legs moving up and down together. No flutter kicking is allowed. A butterfly swimmer must touch the wall with both hands before turning and his or her head must surface within 15 meters of the start and after turns.
Men’s 100m: In Beijing, Michael Phelps beat Serbian Milorad Cavic by 0.01 seconds – the closest finish in Olympic swimming history. Cavic appeared to reach the wall first but Phelps was able to apply enough pressure on the timing pad to stop the clock before him. The pair staged nearly a repeat performance at the 2009 Worlds, with Phelps winning by 0.13 seconds. Phelps also won the event at the 2011 Worlds (Cavic wasn’t there). In London, this event will be all Phelps. He’s joined on the U.S. team by Tyler McGill, whose time of 51.32 at Trials would have given him fifth place in Beijing and fourth at the 2011 Worlds. Cavic will be in London and he’ll probably make the finals, which would set up a rematch of 2008 and 2009.
Men’s 200m: n Beijing, Michael Phelps beat Hungarian Laszlo Cseh in world-record time despite a goggle malfunction that resulted in water filling them up to the point where he could not see in the second 100 meters. Phelps won the race at the 2009 and 2011 World Championships, but a new contender has emgered: China’s Wu Peng. In London, Phelps will probably take it out slow – as he normally does – and we could see Wu in the lead after the opening 50 meters. Being a back-half swimmer, however, Phelps should hit the 100-meter wall in control of the race and he’s expected to take the gold medal.
Women’s 100m: In Beijing, Libby Trickett of Australia won the gold medal ahead of American Christine Magnuson and Australian Jessicah Schipper. Trickett then retired but has since made a comeback, although she did not qualify for London in this event. American Dana Vollmer is the favorite to win gold here. After falling short of qualifying for the 2008 Olympics, she has become the best 100m butterfly swimmer in the world. Vollmer won the world championship in 2011 after a fifth-place result in 2009. A possible spoiler to Vollmer’s plans could be Australian Alicia Coutts.
Women’s 200m: In Beijing, Liu Zige broke the world record and paced China’s 1-2 finish (Jiao Liuyang was second). Australian Jessicah Schipper, who was third in Beijing, won the race at the 2009 Worlds. Jiao was the 2011 Worlds champion. Any number of swimmers could capture gold in London. Aside from the above three, Great Britain’s Ellen Gandy has a solid chance of doing something special. In terms of the Americans, Cammile Adams and Kathleen Hersey earned spots at Olympic Trials. Neither seem to be a legitimate medal threat, but it would not be a huge surprise if one of them makes the final.