I used to get really really winded after one or two rounds of a battle. This is what i've learned.
1. slow the f*#! down. go with the beat. it's easy to get excited and go faster than the beat.
2. remember to breathe. seriously this may seem like a no brainer, but i used to get so involved that i would hold my breath and forget to breathe. an easy thing to do is just to exhale or say something under your breath on every hit.
not all that different from boxing actually if you think about it.

hope that helps