Being an elite athlete requires mastery of mind, body and, occasionally, some unorthodox skills. As part of the December 2024 Total Athlete issue, SI explores how today’s complete competitors are expanding what’s possible with new fitness frontiers, cutting edge technology, mental training and more—from the behemoths of the NFL’s offensive line, to a versatile WNBA veteran, to a special group of athletes who forgo the fundamentals and go against the grain.
Before he steps up to the plate, Cubs outfielder Ian Happ peers at a bull’s-eye sticker affixed to the inside of his batting helmet, just above the earpiece—a quick depth perception exercise that reminds his brain to utilize both eyes while at bat. This small habit is just one element of Happ’s vision-training routine, which he started after posting career lows in batting average (.226), on-base percentage (.323) and OPS (.757) during the 2021 season. A teammate referred him to Ryan Harrison, owner of SlowtheGameDown, a vision performance program based in Irvine, Calif.
“We want people working on our bodies and swings, but if you can’t see the ball, you’re not going to have much success,” Happ says. “I think it’s a big part of what we do and it’s the least [thing] emphasized or trained.”
Indeed, shoulder presses and squats are workout standbys, but exercises for the eyes are often overlooked. That’s where Harrison—who works with athletes in baseball, football and hockey—concentrates his training. The eye contains six muscles that work together to move it in all directions, like the strings on a marionette. They are divided into two groups: the recti, the primary vertical movers when the eye is abducted, or looking away from the nose; and the oblique, used when the eye is adducted, or looking towards the nose. During his initial evaluation with an athlete, Harrison uses a series of tests and drills, most of which originate from another time—and another Harrison. After playing baseball at Cal, Ryan’s father Bill became an eye doctor and later began working with the Royals as a vision-training specialist in 1971. He went on to work with 15 MLB organizations and several NCAA baseball programs before his death in 2019.
“A lot of the stuff we do today is based on what they were doing in the ’70s,” says Ryan. “The technology is updated. But the brain and the eyes haven’t changed. It’s really about how we’re using those skill sets and enhancing them.”
Harrison’s evaluation mainly tests eye movement and motor control, focusing on those six muscles of the eye and how they work together with the brain to execute specific activities, such as following someone’s finger as it moves into different areas of your gaze. One of the tools he uses to assess these vision-processing skills is called the NeuroFit One, a medical-grade device that records, analyzes and measures eye-movement responses to different stimuli using a high-speed camera.
Once Harrison establishes a baseline, he will tailor his training to focus on different vision skills. These include binocularity, also known as eye teaming, which is the ability to focus on an object with both eyes to create a single image and thus, make accurate spatial judgments; and peripheral awareness, or the ability to see objects and movements that are not directly in front of you, which can ultimately allow athletes to react more quickly and with better anticipation.
The first season after working in the program, Happ made his first All-Star team. He hit 45 points higher and added 19 points to his OBP. In the two subsequent years, Happ’s walk rate increased, including a career-high 99 free passes in 2023.
“When you play at this level, the difference between success and failure is [so small],” Happ says. “Fouling the ball straight off or squaring the ball up at 95 or 98 miles per hour is the difference between centimeters. For what we do, as hitters, I think [vision training] is a pretty undervalued part of the whole equation.”
Last offseason, Jacob Stallings was on the verge of baseball oblivion. The veteran catcher had struggled offensively through two seasons with the Marlins, hitting a combined .210 with a .287 OBP after posting solid numbers over six years with the Pirates. Prior to the 2024 season, Stallings, 34, signed a one-year deal with the Rockies. He also met Harrison, who was brought in as a consultant for the team during spring training.
“After the assessment, [Ryan] asked me if I had had any concussions in the past,” says Stallings. He suffered one in 2020 and another in ’21, and considered both very minor. But Harrison’s evaluation revealed something else: When Stallings tried to track a fast-moving object, his right eye would flutter.
Harrison’s program helped fix vision problems Stallings believes were caused by his concussions. The results were stark. After hitting .191 in his final year with the Marlins, Stallings hit .263 with a .357 OBP, jumps of 72 and 79 points, respectively. “It changed the course of my career,” Stallings says.
When quarterback Mason Rudolph started working with Harrison following the 2018 season, initial testing revealed an imbalance with an emphasis on the right eye. In an effort to fix that issue, Harrison put Rudolph (then with the Steelers, now with the Titans) through a drill where he tracked bouncing balls on a projector screen—similar to the old DVD logo on a screensaver—while dropping back in a natural quarterback movement. Then, after Rudolph sustained a concussion in a ’19 game, he worked with Harrison to strengthen his eyes.
“I noticed that I had improved and that my peripheral vision was better,” says Rudolph. “I think it allows you to play around with things in practice, like looking off defenders and holding them until the last minute. I’m not making no-look throws like some of these guys, but it allows you to hold defenders with your eyes and feel people coming into spaces better when you’ve trained that, as opposed to the only reps you’re getting being in practice. I felt like psychologically, I had a little bit of an edge.”
Rudolph isn’t the only NFL player taking advantage of the science. Lions quarterback Jared Goff, Bills tight end Dawson Knox and Chiefs linebacker Drue Tranquill have also worked with Harrison. All told, Harrison estimates he has 20 to 25 current pro athletes in the program at any time. The work is something players can do in person at the Irvine facility, or on their own by using manual and computerized drills.
While the technology continues to evolve, the premise is simple: Any edge an athlete can pick up in judging space and time by strengthening their vision is going to lead to better performance. That much is plain to see.
This article was originally published on www.si.com as Savvy Pro Athletes Are Training This Often Overlooked Muscle .