I encourage everyone to read this article by Matt Chaney (as well as his others) on steroid use in American football. Steroid use in football didn't begin with the San Diego Chargers pro team, or with football players training with Hoffman or Alvin Roy. AAS were prescribed by doctors across the country to players at high school, college, and professional levels.
1960s: Steroid Programs for Football Players, Preps to Pros (Final in a Series)
Steroid programs were underway in the AFL along with the NFL, and at colleges and high schools in the early 1960s, as revealed by news evidence formerly buried in microfilm.
thinksteroids.com