People swim at the start of the annual Lake Zurich crossing swimming event in Zurich, on Aug 22, 2012. The participants swam across Lake Zurich on a 1,500 meters (4,921 ft) track. [Photo/Agencies]

Gaza runner Bahaa al-Farra stretches during a training session in Shati refugee camp in Gaza City, on March 25, 2012. The 19-year-old trains for three hours a day in Gaza's Yarmouk soccer stadium, along the dusty streets and on the beach in well worn trainers that were donated to the Palestine Olympic Committee by wealthy Gulf state, Qatar, as he prepares to race at the London Olympics. [Photo/Agencies]