My friend and gym buddy Ariel recommended going along to a class she goes to at the gym yesterday, so I did. It was a Les Mills class called Body Combat class and boy was it hard work! Taking techniques from various martial arts in a non-contact way, it involved a lot of visualising certain people and punching and kicking at them ;) It lasted 50 minutes, I was absolutely exhausted and woke up this morning feeling like I'd been in an actual fight, and I loved it! I'm going to be adding it once a week along with my running and weight training to get that extra bit of cardio in.
I'd definitely recommend it if you have a class nearby, it's well worth the time!