While speaking about his rookie season with J.J. Redick on the Mind The Game podcast, James revealed that the hardest thing for him to adjust to as a 19-year-old in the NBA was the schedule.

“The best teacher in life is experience. But when I got to the NBA, the biggest adjustment that I had was literally just going from like, ‘Oh s–t, I don’t have to go to class every day,'” James said around the 19:20 mark. “I’m going from a 27-game season to now 82, so like, oh s–t, after 27 games in the NBA, around about 32 games, I’m exhausted. So now, like, what can I do to get the energy back going?”

After being selected by the Cleveland Cavaliers with the No. 1 pick in the 2003 draft, James made an immediate impact. He played 79 games that year and posted averages of 20.9 points, 5.5 rebounds, 5.9 assists and 1.6 steals on his way to being named the 2004 NBA Rookie of the Year.

“As far as when I stepped out on the floor, there wasn’t too much of an adjustment,” he said. “I felt like I was physical enough, I felt like I had the size. I had the speed, obviously. I had the athleticism, obviously.”

Now the NBA’s all-time leading scorer, James has enjoyed a legendary career. He revealed earlier this week that he doesn’t have much time left in the league, but he’s still performing at an incredibly high level as he tries to lead the Lakers to another championship.