All dem people with a pole. This is one of my FAVE pole exercises. Basically you grab on like so, then you lift your legs up, keeping them straight, until they are horizontal like so (I just made a pretty pose hehe). THEN you bring your legs in to your chest and curl up with your abs (i.e. you are trying to do a full invert from this position). Repeat without letting your feet touch the floor.
I GUARANTEE BUTT, ABS/BACK AND ARM BURN. And you increase your grip strength. :D For some reason I get more butt burn when I do it in a straddle instead of straight legs but whatevs.
If this is easy for you, there is a harder one you can do that I still struggle with. ahah. There is also an easier one that works the abs and arms (not so much butt) that I used to do a lot.