ILLUSTRATION 1.1: Calling off the jam.

Banger Sisters vs. Violent Femmes
Originally uploaded by bjmacke (a.k.a. Apron)

This is why I get bruises! When your arms start out above your head, they are going to come down swinging HARD.

And I am pretty sure I am calling it off, not lifting my arms to show I'm not back-blocking - that's the opposing jammer in front of me, that's when the jam ENDS.