Kaley Cuoco is ''obsessed'' with dirt biking.

The 'Big Bang Theory' star has recently been trying out some extreme sports after being encouraged by her boyfriend Karl Cook - who she has been dating for around 18 months - and she cannot get enough of the motorcycle hobby.

She said: ''Karl is a big adventure seeker and he encourages me to do things that are outside of my comfort zone, like mountain biking and dirt biking.

''I did it, and now I'm obsessed, and I had the best time. We did it in Hawaii and of course now I want to be gung ho and do it. He's getting me to be more adventurous than I am.''

Kaley has gushed over her boyfriend, admitting she is ''completely in love'' with him after they bonded over horses.

She said: ''He is totally the guy. I think the common denominator is the horses, it just works for us. We have this special bond so yeah, the animals. He's so real.

''I've never met a kinder human being, he's gentle, and he's real. I'm completely in love with him. Nothing could be better.''

The 31-year-old star - who was married to Ryan Sweeting from 2013 to 2016 - owns three dogs and admitted another one could be coming to live with her if Karl gets his way.

Speaking to 'Entertainment Tonight', she said: ''Karl informed me actually a few days ago that he wanted to rescue another bulldog, so I think we're going to go get another bulldog.

''It doesn't matter at this point, any dog is welcome in my house apparently.''