Consider taking up a martial art. There are a lot of different types to choose from, so just go and watch some classes, and when you're ready, the teacher (sensei) will usually let you join in a few classes for free before signing up.

Or you could try something like boxing. A lot of people also just beat the crap out of their pillows, bed, and other sturdy furniture.

If it's really the arguing that you like, you could join the debate team.