Ríos was the silver medalist at the 1983 Pan American Games and competed at the 1983 World Championships in Athletics later that year, where he was knocked out in the heats stage.
In his only Olympic appearance in 1984, he finished twelfth in his semi-final in the men's steeplechase.
Ríos attended California Polytechnic State University, San Luis Obispo, where he still holds the school record in the Steeplechase set at the USA Outdoor Track and Field Championships in Indianapolis, Indiana at 8:28.89 from 1983.
He was also the Southern California champion at 10,000 meters and the third individual at the State Cross Country championships.
In 2013, he was honored in the Long Beach City College "Hall of Champions.