Kobe Bryant lives by this mantra from his high school English teacher

Retired NBA star Kobe Bryant
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It's been more than two decades since Kobe Bryant graduated from Lower Merion High School, a public school in the suburbs of Philadelphia. But the retired NBA star, now 40, still remembers one teacher in particular: Mr. Fisk, who taught English.

"He had a great quote: 'Rest at the end, not in the middle,'" Bryant told podcast host and best-selling author Lewis Howes on an episode of "The School of Greatness." "That's something I always live by."

Hard work has been a key ingredient in Bryant's recipe for success since he was a teen. The emphasis on perseverance started as a defense mechanism, he told Howes: "In middle and high school, a lot of the kids that I was playing against were inner-city kids. They're looking at me as if, 'OK, this kid is soft. He's from the suburbs of Philadelphia. His father played in the NBA.'"

The challenge for Bryant became, "How can I mentally figure out ways to break you down? How can I show you that, no, I have the edge?"

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His solution was dedication. "We used to have an all-American camp that I used to go to," Bryant recalled. "One of the things I would do is — everybody would be at the cafeteria eating and I'd just go back to the gym. They'd see me leave. … And that was my way of showing them, 'Yeah, maybe I'm from the suburbs, but you're not going to outwork me.'"

He maintained an intense work ethic throughout his career with the Lakers: He often worked out harder and earlier than his peers. And he saw results: He won five NBA championships, collected two Olympic gold medals, earned one NBA MVP title and made Lakers history as the team's all-time leading scorer. He still holds that record.

Today, Bryant runs a venture capital fund with business partner Jeff Stibel and still wakes up before the sun to work out. He's even won an Oscar, for producing the Best Animated Short Film, "Dear Basketball."

As he told Howes, even though his lucrative basketball career is over, "I'm not going to rest. I'm going to keep on pushing now."

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