Dwayne 'The Rock' Johnson found his return to the wrestling ring to be "incredibly hard".

The 52-year-old actor competed in a WWE wrestling ring for the first time in 11 years at WrestleMania 40 - but Dwayne admits that it was a huge challenge at his age.

The Hollywood star - who enjoyed huge success as a wrestler, before switching to the movie industry - told PEOPLE: "It's incredibly hard. The training becomes really extensive, and the training camp becomes extensive."

Dwayne actually embarked on a "eight- to nine-week training camp" before his WrestleMania appearance in April.

He said: "I went [to] training camp for WrestleMania, which was about an eight- to nine-week training camp. It's really fast, and fortunately, I was able to get through it all."

Dwayne previously explained that he will "always be a pro wrestler at heart".

The wrestler-turned-actor admitted that he didn't have any hesitations before making his return to the WWE.

Dwayne - who comes from a family of professional wrestlers - told 'Entertainment Tonight': "I love it. I love what I do, I love this world of wrestling, I love pro wrestling, I was born into pro wrestling, I will always be a pro wrestler at heart and in attitude too."

Dwayne actually joined the board of WWE's parent company, TKO, earlier this year, and he loves having such a hands-on role in the business.

He said: "I'm so grateful to come back in this capacity that I could come back and give to this business and give to the men and women in that locker room, and try and do my little part to do this with everything and create greater opportunities for all of them."