On February 3, the Baltimore Ravens and the San Fransisco 49ers will face off in the 47th Super Bowl. When they sit down to watch fans will see players on the field like the Ravens’s Haloti Ngata, a 6’4”, 340 pound defensive end. Bryant McKinnie, the left tackle for the Ravens, is 6'8" and 360 pounds. Leonard Davis, on the 49ers, is 6’ 6” and 355 pounds. Fans and players alike understand some of the risks that come with two 350 pound men slamming into one another. The hidden, long term risks of repeated head injuries have dominated the football headlines this season. But the risks go beyond torn ligaments and bashed heads. Bigger players also have to deal with the side effects of their sheer size – things like obesity and metabolic disorders, that stay with them long past their playing days.
Bigger is better
Football players have always been big, but today’s players are truly huge. A recent study found that every year since 1942 players at all positions, from quarterbacks to centers, have gotten heavier. The change was most noticeable for linemen - who gained, on average, from .7 to 2 pounds each year. Applied to the whole span of time that the researchers looked at, that's an increase of almost one hundred pounds since 1942. When they looked at what kind of weight that was - muscle or fat - they found that linemen were adding from 0.05 to 0.3 percent fat each year - something like an 11 percent increase in body fat percentage since 1942.
Anecdotally, to long time football fans this seems obvious. Take Roosevelt Brown, a star tackle for the New York Giants from 1953 to 1965. In his career, Brown played in nine Pro Bowls, and was named one of the 100 greatest football players ever by The Sporting News. Brown wasn't a small guy, coming in at 6' 3" and 255 pounds. But stacked up against today's tackles, he wouldn’t stand a chance. Flozell Adams, now a free agent but a long time offensive tackle for the Dallas Cowboys has five Pro Bowls under his belt. He's 6'7" and 340 pounds. Just four inches taller, but nearly 100 pounds heavier. There are all sorts of examples like this. Compare star centers - Chuck Bednarik from the 1950's and Andre Gurode today and you see the same thing. Bednarik was 6'3" and 233 pounds - Gurode is 6'4" and 318.
In fact, despite being some of the top athletes in the game, some active NFL players are clinically obese. "From a coaching standpoint, it makes a lot of sense to have the biggest possible person that you can have," says Dale Wagner, a researcher at Utah State University who looked at the prevalence of obesity in NCAA football players. One study, published in the Journal of the American Medical Association, looked at body mass index in NFL players. They concluded that 97 percent of current NFL players were overweight, and 56 percent of them qualified as obese. Wagner says that using BMI on a professional athlete is misleading - the index isn't designed to characterize people who spend the majority of their time working out. But if the NFL is anything like the NCAA, the percentage of obese players is probably still something like 15 percent.
The push for bulk
There are a lot of reasons why football players are bigger now than they used to be, says Jeffrey Potteiger, researcher at Grand Valley State University, who recently published a study tracking the size of football players from 1942 to 2011. Some are obvious: "we've gotten better at how we train players, we've gotten better at how we feed players." In 1978, the National Strength and Conditioning Association was founded by a group of strength coaches to help codify and legitimize a vast-growing profession. Hundreds of studies have been done to understand exactly what combination of protein and carbohydrates will give athletes the edge. Combined with likely illicit steroid use, better training and better food simply means bigger players.
But it's not just a technological improvement. Rule changes in the NFL likely contributed to incentivizing a bigger heavier player too. Up until the 1970s, it was legal for players to block below the waist - a move known as "chop blocking." But in 1970, the Rules Committee voted unanimously, 23-0, to ban chop blocks, calling the move "unethical" because it seemed to be causing serious knee and ankle injuries. The result was probably fewer knee and ankle injuries, but the rule change precipitated a huge boom in weight lifting. Players now needed to be big and sturdy, and extend their arms out straight to block above the waist.
The combination of this rule change and the advent of modern strength training seems to have set football on a steady course towards bigger and bigger players. And many coaches seem locked into this trajectory. "It's like an arms race," says Potteiger, "whoever can be the biggest strongest person out there gains the advantage on the field." When one team has Andre Gurode at center, the other team has to respond by putting a similarly sized player against him. When your defense is playing against a 6'7", 350 pound Flozell Adams, they need someone who can keep up. "Because in a jump ball the 6' 7" guy is always going to win," says Potteiger. Wagner agrees, saying that if one team has a bigger stronger line, they're going to have the advantage. And if coaches are comparing two similar players, they're almost always going to choose the larger one. "If they can run the same 40 yard dash, if they can jump just as high, they're going to pick the bigger person," says Wagner.
Of course, this push towards heavier, bigger players doesn't just impact the NFL. As professional players get bigger, so do college and high school players. The University of Florida has 16 players over 300 pounds on their roster. Elder High School, which has a famed football program, has ten players that weigh in over 250 pounds. And the earlier they start, Wagner says, the more likely they are to be able to get really big. "Just consider that most of these folks have been training through high school, through college, maybe 10 years of training to get to that point," Wagner says.