When I press my finger, even with relatively little force, into beef or chicken (say, at a grocery store), the indentation remains.
When I poke a cow with my finger, the indentation does not remain. When I squeeze my own arm, even with the same (or greater) amount of force used to alter the shape of meat with my finger, my arm remains the same shape afterwards.
What is the difference between dead and living muscle tissue, with respect to mechanisms that allow it to maintain its shape? Does living muscle tissue somehow actively maintain its shape while dead tissue cannot? Is it something more passive, such as a breakdown of something in dead muscle tissue that makes it more malleable (and if so, what)?