I started boxing a few months ago, and it's definitely been the hardest workout I've ever done!

The worst part for me is sparring... I boxed 3 two-minute rounds today and literally thought I was going to die. Towards the end, I was hoping my sparring partner would just knock me out. Guess I need to crank up the cardio if I'm going to survive this workout!

More likely though is that I will just watch the training scene in Rocky on YouTube, and pretend that I'm doing cardio. I need to find a pure cardio workout that I enjoy!

What's the hardest workout you've ever done?