LeBron James was impressed by the sheer speed of the Houston Rockets after they dished out a 112-97 defeat to his Los Angeles Lakers in Game 1 of the Western Conference semifinals.

Rockets star James Harden went 12-of-20 from the field for a game-high 36 points as the Lakers were outplayed and overrun on Friday.

It was an eye-opener for James and his team-mates, who will at least be better prepared for the task awaiting them in Game 2.

Assessing what had made the Rockets so dominant, James said: "I think it's the speed.

"They play with a lot of speed both offensively and defensively. And you can watch it on film and you can see it on film; until you get out there and get a feel for it [you cannot comprehend it].

"That's what we did tonight. We got a feel for their speed, and we should be fully aware of that going into Game 2."

The Lakers will attempt to level the series on Sunday and James, who put up 20 points, added: "How do you adjust to a team's speed? You understand that it's not just about the legs moving; it's about the hands moving as well.

"They're great with their hands. You understand that if you have the turnover, you can't really react; you have to get back, quick twitch. Quick-twitch plays, because they're very, extremely fast.

"You adjust to that by playing against it. It was, 'Okay, we need to play them again'.

"There's no way you can simulate that speed."