FILE - In this Dec. 17, 2010 file picture Switzerland's Silvan Zurbriggen speeds down the course to take the sixth place in an alpine ski World Cup super g race in Val Gardena, Italy. Olympic medalist Silvan Zurbriggen says Wednesday April 1, 2015 he has retired from Alpine skiing at age 33 because of persistent back injuries. (AP Photo/Alessandro Trovati,file)