Not moving
The lack of movement can have just as much impact as movement. A freeze frameA tableau is a single freeze frame, a still image. Tableaux refers to more than one tableau. or still image with an emotional stillness can be very powerful. The power comes from the interruption of what is natural. We expect movement, so stillness is an implicit shock. It makes us look at what is happening, taking the time afforded by the stillness to interpret the action. This can also be used for marking the moment to explore a key moment in time. It also creates contrast and varies pace, keeping the work interesting. Look at Explorative strategies for further examples.
Tension
Tension can be very productive but unwanted tension is something that an actor has to learn to avoid. A movement class at drama school won鈥檛 just teach you how to move effectively within a particular role, but also how to move effectively within your own body. You need to use tension to create emotional strength in your work. But don鈥檛 let tension or stress that comes from strain or embarrassment inhibit you.