THE FIRST TIME Roo Yori saw NBC's extreme obstacle-course competition, American Ninja Warrior, he had one reaction: That would be so cool to try. Such impulses have not only fueled the popularity of the show, which kicks off Season 9 on June 12, they have also led to an explosion of ninja wannabes.
How much so? Yori, 40, first watched Season 6, which aired in 2014. When it was over, a call for applicants for the next season yielded 5,000 hopefuls. This year 77,000 people applied. And in '15, when Yori, an assistant lab supervisor at the Mayo Clinic in Rochester, Minn., started training in earnest, he had to drive more than two hours to what was, as far as he knows, the only ninja gym—with apparatuses that mimic the show's challenges—in the state. "It was really just a bunch of guys in a converted barn," he says. Today he's aware of four professionally outfitted such gyms in the Twin Cities and another in St. Cloud.
In Yori's case the driving paid off. In 2016, he was selected for the show. The winner of a disk-catching world championship in '06 with one of his dogs, a pit bull named Wallace, and also the owner of Hector, a scarred refugee from Michael Vick's dogfighting operation, Yori competed as the K9 Ninja and made it all the way to the finals. "It's one of the few competitive events in which all the participants help each other out," he says. "It's everyone versus the course, which is a really positive atmosphere."
Yori was asked back, and he stepped up his training for Season 9. A four-year soccer player at Division III St. Mary's University of Minnesota, he took to the obstacles that required balance, foot speed and leg explosion, but he's had to work hard to improve his finger, hand and arm strength to master the many hanging or swinging challenges. "The obstacles are built to test a wide range of abilities," he says. "If you have a weakness, they'll find it, and you never know what they're going to throw at you."
That, of course, is what makes it so cool in the first place.
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K9 Ninja Roo Yori's regimen for building hand strength
Throw in the Towel
Throw a towel over a pull-up bar, get a good grip of one end in each of your hands, and do three sets of 10 pull-ups.
Hook your fingertips over the molding on top of a door frame—make sure it's secure—and do another three sets of 10 pull-ups.
To work the extender muscles, clump your fingers together, thumb tucked underneath. Wrap a rubber band around all five, then spread them open. Do three sets of 10.
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