Ansel Elgort only works out to ''keep up'' with his girlfriend Violetta Komyshan.

The 23-year-old actor is believed to have been dating the ballerina since 2012, and although the couple briefly parted two years later they swiftly rekindled their romance five months later, and the 'Baby Driver' hunk has been taking rock climbing classes at Brooklyn Boulders to keep his lover interested.

Speaking to E! News about his relationship with the 21-year-old beauty, the star said: ''I need to go to Brooklyn Boulders and work out so I can keep up with her.

''[Violetta exercises] all day, every day anyway.''

The 'The Fault in Our Stars' actor - who met his partner when they were studying at New York's Laguardia institute -regularly posts photographs of Violetta and gushes about his girlfriend on social media.

When quizzed about a recent image Ansel shared of Violetta in her dancing attire on his Instagram account, he continued to sing her praises even more.

He said: ''Oh, yeah. That's a good photo of her, right?''

And Ansel is not shy about opening up about his intimate moments with Violetta, as he previously admitted he has ''amazing sex'' with his high school sweetheart, although he had ''no clue'' what he was doing when he lost his virginity aged 14.

Speaking previously, he said: ''I had no clue what I was doing, and neither did the girl.

''I prefer to be with someone I can trust. I'm more into that.

''I think I could say this: If you like someone and the sex is really good and you enjoy spending time together, why wouldn't you make that person your girlfriend? Why go around dating random girls and having terrible sex when you can be with someone you really like?''