The NFL gospel that bigger is better can be proved any given Sunday. What Bob Goldman wonders is how many Sundays the guarantee is good for.
Nearly 10 years ago, the author of ''Death in the Locker Room'' warned that super-sizing pro football was a recipe for danger. The season before he presented a paper on the subject to the National Academy of Sports Medicine, there were 38 players in the league weighing 300 pounds or more. Last year, there were 280. All but one of the 31 teams averaged at least 300 pounds across the offensive line.
''The dangers are the same, only there are more people exposed,'' Goldman said Sunday. ''A heart set up to support a man weighing 220 is facing a lot more stress supporting one who weighs 320. Pick any of the body's systems -- skeletal, muscular, circulatory -- the same is true across the board.''
It's been a rocky few days for the sport. The death of Vikings Pro Bowl tackle Korey Stringer of complications from heat stroke called attention to the number of college and high school athletes who suffered similar fates -- 18 deaths since 1995 -- and forced the NFL to rethink the strategy of brutal practices in brutal weather.
It also called into question whether players are getting too big.
Look at the linemen inducted in the Hall of Fame last weekend. Ron Yary, who left the game in 1982, played his entire career at tackle weighing around 260 pounds. Jackie Slater, who played from 1976-95 with the Rams, rarely pushed 280. Ditto for Mike Munchak, who got out in 1993.
Even recently, most 300-pounders were guys who didn't know when to push back from the table. Not long after ex-Atlanta coach Jerry Glanville inherited huge tackle Lincoln Kennedy, he answered a question about the lineman's potential this way: ''He can be a great player in this league for a long time if he learns two words: 'I'm full.'''
But today's 300-pounder is rarely an accident. They're bona fide athletes with high muscle mass and 15 percent or lower body fat, beneficiaries of continuing advances in nutrition, conditioning and weight training.
''That's the way they're coming from the high schools,'' said Munchak, now working as a line coach for the Tennessee Titans. ''Most people believe you've got to be 320 and 6-foot-7. They're coming in bigger now, but most of them are in pretty good shape. It's evolution.''
Goldman, an expert in the science of how players get bigger, studied linemen in college from 1950 through 1990. Through the first three decades, the average weight increased by about 10 pounds. From 1980 to 1990, however, it jumped 20 pounds.
Goldman, one of the leading researchers in steroid and drug abuse, makes no claims about the number of steroid users at any level, other than to say he suspects it's higher than what drug tests turn up. But he also believes most of the new generation came by their bulk honestly.
''Look at the salary increases over the same period I tracked weight,'' he said. ''Money is a powerful incentive. If you can develop a lineman who's 6-8 and 330 with the same speed and agility of guy who's 250, who's more dangerous?''
Yet, in the wake of so many heat-related deaths, maybe the league should also consider whether those new, larger athletes face different dangers.
''The game evolves,'' said George Young, a former pro lineman, New York Giants executive and now the NFL's senior vice president for football operations. ''If we find out something isn't working well, we change the rules. Then we revisit the issue. It may be that we have to rethink how we got here and whether it serves the largest good.''
What started the size craze along the offensive line was a rule change in the mid-1970s. The Pittsburgh Steelers were dominating and the league was stuck with a spate of 10-7 results. To kick-start the passing game, offensive linemen were allowed to extend their arms to block.
At the same time, cornerbacks were no longer allowed to jam receivers at the line of scrimmage. That rule change produced the opposite effect; receivers and cornerbacks have gotten smaller over the same period, in part because the hand-to-hand combat at the line is no longer part of either job description.
''When you couldn't move your hands away from your chest, you needed faster footwork,'' said Young, who also chaired the league's competition committee for several years. ''Big heavy guys just weren't agile enough. But now the length of your arms is more important than the quickness of your feet. And big guys today are likely to have both.''
But that's not all they're likely to have.
''Stroke, high blood pressure, more traumatic joint injuries, cardiovascular problems -- the risk factors for all those conditions,'' Goldman said, ''increase with size.''
Jim Litke is the national sports columnist for The Associated Press. Write to him at firstname.lastname@example.org
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