Since your ability to use your hips to bridge is such a big part of escaping from Side Control or Mount it only makes sense to train this movement…a lot. Most schools use some form of bridging as part of their warm ups and I encourage Jiu-Jiteiros to include different types of bridging in their workouts.
Like my professor tells me all the time – BJJ is a game of space and you are either creating it or occupying it. The problem is that when someone is on top of you occupying a lot of space there it can be tough to create enough for you to move.
One of the most important factors in creating space on bottom is how well you can use your hips. Sure, you need to have good frames and basic position but when it comes time to move and make the space you need to escape then the hips are where it’s at.
One of my favorite images from history is when the Persian king Xerxes faces off with the famous 300 Spartans at Thermopylae…but it isn’t any of the battles or famous one liners that I think of.