Winner of the USA Olympic Trials in 1976, he did not gain a medal in the individual event (he came fifth), but did become a winner of a gold medal in 4 × 400 m Men's relay race with Herman Frazier, Benny Brown, and Fred Newhouse at the 1976 Montreal Olympic Games. In the 1970s he competed for the UCLA for several years. In 1977 he ran on the 1977 IAAF Athletics World Cup, anchoring the 4 × 400 m relay team to what appeared to be a runaway victory when he collapsed on the track with a severely pulled hamstring 150m from the finish. This unfortunate injury denied the USA a seemingly certain victory in the team competition, the victory instead going to East Germany. Parks did not compete again that season, but did return in 1978 to again capture the national title at 400 m.