MIAMI -- The only thing that keeps LeBron James up worrying at night is basketball, which simultaneously makes perfect sense and no sense.

On one hand, he's the game's best player.

On the other, he's rarely impressed with himself.

Even after a year like 2013 -- when a spectacular wedding, a second NBA championship and a fourth MVP award were among the many highlights enjoyed by the Miami Heat star -- he still is, as he puts it, striving for greatness. Or, technically, more greatness, since his enormous list of accomplishments just keeps growing.

James was announced Thursday as The Associated Press' 2013 Male Athlete of the Year, becoming the third basketball player to capture the award that has been annually awarded since 1931. James received 31 of 96 votes cast in a poll of news organizations, beating Peyton Manning (20) and Jimmie Johnson (7).

"I'm chasing something and it's bigger than me as a basketball player," James told the AP. "I believe my calling is much higher than being a basketball player. I can inspire people. Youth is huge to me. If I can get kids to look at me as a role model, as a leader, a superhero ... those things mean so much, and that's what I think I was built for. I was put here for this lovely game of basketball, but I don't think this is the biggest role that I'm going to have."

Past winners include Joe Louis, Jesse Owens, Muhammad Ali, Carl Lewis, Joe Montana, Tiger Woods and Michael Phelps. Serena Williams was the AP Female Athlete of the Year, announced Wednesday.

James joins Michael Jordan and Larry Bird as NBA players to win the award.

"I don't think I've changed much this year," James said. "I've just improved and continued to improve on being more than just as a basketball player. I've matured as a leader, as a father, as a husband, as a friend."