고 달려오다

come running; have kept going

-고 attaches whatever accompanied the running and 달려오다 is coming at speed toward the speaker: 일하다 말고 달려왔어요 'I dropped work and ran over', 깃발을 들고 달려온다 'comes charging with a flag'. It also has a figurative use for a long stretch of effort: 20년 동안 멈추지 않고 달려온 'twenty years without stopping', 앞만 보고 달려왔던 'kept running with eyes only on what's ahead'.