The AP's analysis corrected for the fact that players in different positions have different body types, so speedy wide receivers weren't compared to bulkier offensive tackles. It could not assess each player's physical makeup, such as how much weight gain was muscle versus fat, one indicator of steroid use. In the most extreme case in the AP analysis, the probability that a player put on so much weight compared with other players was so rare that the odds statistically were roughly the same as an NFL quarterback throwing 12 passing touchdowns or an NFL running back rushing for 600 yards in one game.
In nearly all the rarest cases of weight gain in the AP study, players were offensive or defensive linemen, hulking giants who tower above 6-foot-3 and weigh 300 pounds or more. Four of those players interviewed by the AP said that they never used steroids and gained weight through dramatic increases in eating, up to six meals a day. Two said they were aware of other players using steroids.
"I just ate. I ate 5-6 times a day," said Clint Oldenburg, who played for Colorado State starting in 2002 and for five years in the NFL. Oldenburg's weight increased over four years from 212 to 290, including a one-year gain of 53 pounds, which he attributed to diet and two hours of weight lifting daily. "It wasn't as difficult as you think. I just ate anything."
Oldenburg told the AP he was surprised at the scope of steroid use in college football, even in Colorado State's locker room. "College performance enhancers were more prevalent than I thought," he said. "There were a lot of guys even on my team that were using." He declined to identify any of them.
The AP found more than 4,700 players — or about 7 percent of all players — who gained more than 20 pounds overall in a single year. It was common for the athletes to gain 10, 15 and up to 20 pounds in their first year under a rigorous regimen of weightlifting and diet. Others gained 25, 35 and 40 pounds in a season. In roughly 100 cases, players packed on as much 80 pounds in a single year.
In at least 11 instances, players that AP identified as packing on significant weight in college went on to fail NFL drug tests. But pro football's confidentiality rules make it impossible to know for certain which drugs were used and how many others failed tests that never became public.
What is bubbling under the surface in college football, which helps elite athletes gain unusual amounts of weight? Without access to detailed information about each player's body composition, drug testing and workout regimen, which schools do not release, it's impossible to say with certainty what's behind the trend. But Catlin has little doubt: It is steroids.
"It's not brain surgery to figure out what's going on," he said. "To me, it's very clear."
Football's most infamous steroid user was Lyle Alzado, who became a star NFL defensive end in the 1970s and '80s before he admitted to juicing his entire career. He started in college, where the 190-pound freshman gained 40 pounds in one year. It was a 21 percent jump in body mass, a tremendous gain that far exceeded what researchers have seen in controlled, short-term studies of steroid use by athletes. Alzado died of brain cancer in 1992.
The AP found more than 130 big-time college football players who showed comparable one-year gains in the past decade. Students posted such extraordinary weight gains across the country, in every conference, in nearly every school. Many of them eclipsed Alzado and gained 25, 35, even 40 percent of their body mass.
Even though testers consider rapid weight gain suspicious, in practice it doesn't result in testing. Ben Lamaak, who arrived at Iowa State in 2006, said he weighed 225 pounds in high school and 262 pounds in the summer of his freshman year on the Cyclones football team. A year later, official rosters showed the former basketball player from Cedar Rapids weighed 306, a gain of 81 pounds since high school. He graduated as a 320-pound offensive lineman and said he did it all naturally.