 Macharinyang made his first appearances on the track in 2004 and after a fourth place over 10,000 metres at the 2004 World Junior Championships in Athletics, he went on to take the silver medal at the 2005 African Junior Athletics Championships.He moved up to the senior ranks at the 2006 IAAF World Cross Country Championships and helped Kenya to the team medal with his sixth-place finish in the long race.Further team golds came at the 2007 and 2008 events, where he was fifth and eleventh overall, respectively.