Celebrity trainer Tony Horton says this is his absolute favorite type of workout

Tony Horton's workout programs are famously varied.

The most renowned of these, P90X, includes a mix of all sorts of exercises. One day you are weight training, the next session might be yoga, and then you get hit with a day of cardiovascular-heavy, mixed martial arts-style moves.

During the workouts he seems to have an intense passion for every single exercise he teaches.

So when we talked to him recently we couldn't help but ask what kind of exercise - behind the camera - is his personal favorite?

Here's what he told us:

"I like anything and everything that feels like a gymnastics workout. I love climbing ropes and dip walks on parallel bars… high bars and rings. I've always been an admirer of the fitness of a gymnast - it's so impressive to me. And I would say number two would be track athletes 'cause I love the physique of a track athlete - I mean they're very similar but doing very different things.

"It's all "fast-twitch" exercise but different kinds of fast-twitch exercise. So, like a long run to me or a half marathon or a 10K, it's just not who I am! It kind of depends on your genetics. Some people are just born to run and others are born to do a 90-second high bar routine.

"I love rock climbing and I love rope climbing, I love that kind of stuff, but I also train my weaknesses which is my lower half and endurance with my legs 'cause I'm a skier. So you know, on Monday night I did an hour and 15 minute plyometric routine which I absolutely despise, because it's just so taxing. You're just bent over in between exercises heaving - heaving in air.

"But when it's done, my 56-year old legs are infinitely more powerful and explosive, and my lungs and my heart just have a greater capacity to being able to fly down a mountain as fast as I want, and that's exciting. So sometimes you have to put in the work in the arenas where you're not that thrilled because it helps you be a better athlete, it helps you perform, it helps you have experiences you wouldn't have otherwise."