Coogan was coached at the University of Maryland by Charles Florence Torpey, who headed the Men's and Women's running teams at La Salle University until his untimely death. While in college, Coogan specialized in the steeplechase. Coogan was the first Massachusetts native to run the mile in under four minutes. In March 1995, at the Pan-American Games (Mar del Plata, Argentina), Coogan earned the silver medal in the Marathon, in a time of 2:15:21. He ran the marathon at the 1996 Summer Olympics in Atlanta, placing 41st with a time of 2:20:27, after placing second in the U.S. Olympic Trials Marathon with at time of 2:13:05 (his lifetime best). He also placed third in the U.S. 2000 Olympic Trials Marathon with a time of 2:17:04, but did not compete in the 2000 Sydney Olympics because he did not achieve the Olympic "A" standard qualifying time. He retired from competitive running in 2004.