As Marcus Mariota talks about his preparation for the NFL, he underscores an important concept of working out: It's not just about putting time in the gym. It's about having a purpose so that you make the most of your time in the gym.

"I do it for my family, where I come from and my friends," Mariota says. "And if I can represent that every single day whether it's training, watching film, doing all the little things, it's going to allow me to be motivated and do the best I can for them."

Mariota, who won the Heisman Trophy last season as Oregon quarterback, also emphasizes the pride in his Hawaiian heritage and how its culture is based on respect for family and having an appreciation for what you have.

With Mariota's preparation in advance of the NFL draft combined with Oregon's status as a flagship Nike school, he was an obvious choice to be featured in Nike Training's new documentary series. The opening episode featured Rory McIlroy shortly before the Masters.

A theme of the series is understanding how athletes continue to challenge themselves, and Mariota mentions wanting to turn weaknesses into strengths. Having a mindset that is receptive to constructive criticism is often a huge part of the battle.

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