Staggered start to avoid getting hit early on. Once out of the gate and staggered it's every man for himself to the finish. You can kick and punch, no biting. You are DQ if you are caught double teaming someone, no submissions.
It would add an interesting dynamic making people run as fast as they can to avoid getting the crap knocked out of them, I think we would see a completely different type of athletic build emerge in a race like this.
It would be interesting seeing people intentionally not running in packs.
Thoughts?