Whats the difference between these martingales?

I warm up in German Martingales on my barrel horse before I go in for my run. He's kinda a hot head when he's at rodeo's so it really helps to collect him and keep his nose out of the air. Then, when I'm just about ready to go in for my run, I switch bridles. It works more like a correction this way rather than a permanent fix for the problem. The running martingale isn't bad, but it seems more constrictive to the horse than the germans.