Madonna falls during her performance in Lisbon

In the below video, Madonna was performing in Lisbon on September 14th.  She was seen air humping a guitar and when she got up on the stage, she fell down on her butt.

The falling down action happens at around the :49 second mark.  You'd think she would've gotten over resorting to such tactics at her age.  I mean, she does look great for her age, but who wants to see a 50-year-old rubbing up against a guitar?