If well-formed and well-delivered argumentation is what you are looking for, then your sport is extemporaneous speaking (extemp, for short). You get 30 minutes to prepare a 7-minute speech on a topic provided on the spot. There’s no real benefit to speaking quickly and you are judged on both the quality of your arguments and your presentation style.

A lot of debaters cross over and do extemp on off weekends.