A question for comics veterans.

On another forum, I was talking about the Avengers movie, and various stuff that I wasn't clear on. The discussion went back and forth, and along the way, someone posted a page from a comic about Captain America (or the "new" Captain America, whatever that means; I didn't ask for context because it would probably be too mind-numbingly confusing) training with his shield. The point was that if anyone in comics trained hard enough, they could also throw the shield like Captain America, and thus it did not count as a superpower.

One panel on that page kind of derailed my train of thought, however:



What is happening to Captain America's torso?