NEW ORLEANS — Neither starting quarterback in Super Bowl XLVII will win any Mr. Universe competition. Baltimore’s Joe Flacco boasts the muscle tone of an insurance salesman. San Francisco’s Colin Kaepernick looks more like a surfer. Both are tall and gangly and somewhat awkward, built more like cyclists than football players.
Yet these quarterbacks also possess two of the strongest arms in the National Football League, $2 million limbs that draw hyperbolic comparisons to cannons and rifles and catapults, basically anything that shoots objects really far or really fast.
The matchup of two physically unimposing players who are also so physically gifted underscores important matters in regard to throwing mechanics and the term “arm strength." The latter is something of a misnomer; arm strength has little to do with the size of a quarterback’s biceps or the actual strength of the arm. The former involves the entire body and starts not with the arm but with the feet.
Case in point: Flacco. Case in point, Part 2: Kaepernick.
“Look at someone like John Elway, like Brett Favre," said Jim Miller, a retired quarterback and an analyst for SiriusXM NFL Radio.
“They could do physically what other players could not do. Both Colin and Joe Flacco are like that."
Growing up, Kaepernick played baseball. Naturally, he pitched. His fastball reached 94 mph, and he threw two no-hitters in high school. The Chicago Cubs drafted him despite his greater interest in football, which seemed misguided way back then.
Kaepernick received one offer of an NCAA Division I football scholarship, from Nevada. He blew away the Wolf Pack coaches in only one regard: arm strength.
“That’s the one thing that stood out," said Chris Ault, his college coach. “He had a gun. His passes actually whistled."
Kaepernick’s throwing motion, though, left much to be desired. He delivered passes sidearm, without an arc. Early in his career, Kaepernick threw often while rolling right, because he could easily launch the ball deep and back across the field. One of his darts left an imprint of laces on a receiver. Another hit a tight end on the face mask from more than 50 yards away.
The 49ers tell similar stories of an arm they have come to fear in practice and revere in games. Receiver Michael Crabtree said players would rotate back in line during passing drills to avoid Kaepernick’s turn to throw. Tight end Vernon Davis described Kaepernick as a “freak," adding, “He’ll take your fingers off if you don’t watch it." Davis also said that sometimes, he needed to chase Kaepernick from the weight room.
Flacco’s arm strength is less obvious but no less potent. He also played some baseball. He once fired a 40-yard out route against Miami that traveled no more than 6 feet off the ground, toward a receiver near the sideline, according to Gil Brandt, a longtime NFL personnel evaluator and a SiriusXM analyst. Flacco’s 70-yard touchdown pass to receiver Jacoby Jones this postseason traveled beyond where Denver’s secondary believed Flacco could heave it. Safety Rahim Moore fell as the ball sailed over his head.
Despite Flacco’s and Kaepernick’s ability to throw far and fast, however, Brandt and others argued that arm strength on its own garnered too much attention. When Brandt worked for the Cowboys, they used a radar gun on potential prospects. One player, whose name he could not recall, registered throws at 60 mph. Phil Simms clocked in at 49.
Guess how that turned out.
Brandt was more interested in quarterbacks who threw accurate passes, who had strong work ethics, who did not linger on mistakes. He ranked arm strength as the eighth or ninth most fundamental attribute in a quarterback. For every rifle-armed Elway, there was a Joe Montana, king of the soft touch. Brandt said Rudy Bukich was the hardest thrower he ever saw. Bukich played 14 seasons in the 1950s and 1960s, but he threw more interceptions than touchdowns.
“Arm strength is not as important as you’re often led to believe," Brandt said.
It helps, though. Just ask Warren Moon. He ranked arm strength, after accuracy and the ability to make every throw, third among his most important attributes. He could zing passes accurately more than 50 yards. This helped carry him into the Pro Football Hall of Fame.
Moon knew his arm strength came from his throwing motion, not his figurative guns. That is why he read books by Nolan Ryan and Orel Hershiser, why he studied Roger Clemens’ training methods. The throwing motion, Moon said, was like a concert, with so many disparate parts in harmony.
Dr. Glenn Fleisig, the research director at the American Sports Medicine Institute, a biomechanics research laboratory, has studied and analyzed such matters, mostly in regard to pitchers but also for quarterbacks. In one study, Fleisig’s team looked at both throwing motions to determine whether it was helpful for high school and college athletes to pitch and play quarterback at the same time. They also studied Texas Rangers pitchers, who threw footballs to warm up.
The researchers found the throwing motions largely similar. Quarterbacks held the ball closer to their heads, stood more upright, took shorter strides. The researchers studied what they called “optimal" football mechanics, throws made during drop-backs, not off balance or on the run. They found that both pitchers and quarterbacks planted their feet, rotated their hips and upper trunks, and flipped their shoulders forward, creating a whiplike motion.
“It’s the full body, not just the arm," Fleisig said. “It’s a kinetic chain, a series of coordinated events. The arm is actually the last part of that chain."
Fleisig’s team found that throwing a football was less stressful than throwing a baseball, that it was less harmful to the arm. Still, the research did not support the idea that athletes would benefit from throwing baseballs and footballs during the same season.
It did, however, reinforce the notion that a quarterback’s ability to throw far or fast should be defined as arm power, not arm strength. Strength refers more to force. Power is force multiplied by velocity. This is high school physics, translated into the NFL.
“Quarterbacks need power, which is different than strength," Fleisig said. “In my business, we see thousands of throwing athletes without their shirts on. They don’t look like muscleheads. They don’t have strength, necessarily. But they have power."
If arm power is not the most important trait in a quarterback, it still factors greatly into how teams design their offenses. A stronger-armed passer allows coordinators more options; they can use more of the field. The passer’s throws are faster but flatter, and they are often harder to haul in.
This is evident in the modern NFL, which features more downfield passing than when the short passes of the West Coast offense, all that precision and timing, ruled. Last season, three quarterbacks threw for more than 5,000 yards. None did so in 1990 or in 2000.
Five quarterbacks tossed more than 30 touchdown passes last season. In 1990, that number was two; in 2000, three.
Baltimore in particular is indicative of this trend. The Ravens like to run and run and run and then let Flacco strike deep. He might attempt this six times a game, or eight, or four. But because of the potential for a pass-interference call, which Moon noted was far higher than in his day, and because of the payoff from a long complete pass, such attempts carry a great reward. A weaker-armed quarterback is more limited. So is that quarterback’s offense.
As receivers become taller, stronger and faster, as more athletes play quarterback, as fewer teams run the ball as often, as the rules change to favor the offense, “the ability to throw deep," Moon said, “becomes even more important."
Perhaps the country will see that in the Super Bowl, when Flacco and Kaepernick, two skinny, unimposing men, launch passes in high arcs, or whiz bullets between defenders.
Strong arms, those two. Not arm strength.