Amundson came to Iowa State to participate in football and track. The back earned seven letters as a Cyclone. The four-time track letterwinner owned the ISU discus record, but football gained him the most acclaim. As a running back, Amundson led the Cyclones to their first bowl berth in 1971. The tailback rushed for a then-record 1,260 yards and 15 touchdowns to lead ISU’s charge to the Sun Bowl. At quarterback in 1972, Amundson became the first Cyclone to top 2,000 yards of total offense in a season. His 2,387 yards set a Big Eight Conference mark and earned him Big Eight Player-of-the-Year honors, beating out Nebraska’s Heisman Trophy winner Johnny Rodgers. He was a first-team All-America selection by Gold Sheet of Los Angeles.