 Complete the following phrase:  Kipchoge won his first individual world championship title in 2003 by winning the junior race at the IAAF World Cross Country Championships and setting a world junior record over 5000 m on the track. At the age of eighteen, he became the senior 5000 m world champion at the 2003 World Championships in Athletics with a championships record, then followed with an Olympic bronze for Kenya in 2004 and a bronze at the 