Use of steroids "is rampant within the National Football League," with perhaps three-fourths of linemen, linebackers and tight ends using the muscle-building drugs in a desperate effort to stay competitive, says All-Pro tackle Bill Fralic.

"Steroid use in football represents a vicious cycle," the Atlanta Falcon player told a Senate committee Tuesday. "I know there are many players in high school, college and the NFL who want to stop using steroids, but they can't or won't because they don't believe they can be competitive without them."The Senate Judiciary Committee also heard an estimate from former Pittsburgh Steeler Steve Courson that at least half of pro players at so-called line-of-scrimmage positions use steroids.

The estimates made by the two players, however, were disputed by two head coaches who also appeared as witnesses, Marty Schottenheimer of the Kansas City Chiefs and Chuck Noll of the Steelers.

It was the committee's second hearing this year on the muscle-building substances, initially used by body builders and power lifters, which were introduced into the NFL in the 1960s when weight training became commonplace.

A bill to ban steroids from the mail and designate them a controlled substance like narcotic drugs has been introduced by committee Chairman Joseph Biden, D-Del., and member Sen. Strom Thurmond, R-S.C.

But witnesses could not agree on how widespread the problem is.

NFL Commissioner Pete Rozelle cited an official league estimate that 6 percent to 7 percent of players use steroids, but conceded that figure might not be accurate.

"I thought that's a low figure . . . I thought it might be higher," Rozelle said.

Biden asked Schottenheimer and Noll to comment on estimates that 50 percent to 70 percent of NFL players use steroids.

"I would have difficulty, Senator, in imagining that it would be that high," said Schottenheimer.

"I can't imagine that figure as being completely accurate," said Noll.

But Fralic estimated that "exclusive of quarterbacks, running backs and wide receivers, it's probably 75 percent." He said steroid use was far more prevalant among offensive linemen, defensive linemen, linebackers and tight ends. Courson also said positions requiring bulk and muscle along the line of scrimmage are the ones with the most steroid users - at least 50 percent among linemen.

"NFL owners can't grasp this problem," Fralic said. "They haven't been living in the middle of the steroid madness. They can't see their friends affected by it."