The model figure above stands rigid and straight. A basic position in which the body is much more relaxed is the contraposto (counter-position).
In the contrapost0, the line of the hips is opposite (contra) to that of the shoulders (drawn in red here). Try standing in such a position yourself, it is very easy. You mainly rest on one leg (standing leg) and your other leg is relaxed (pivot leg), bent or not. The foot of the supporting leg is always directly below the head (see the vertical red axis).
Exercise: Try drawing a human figure in a contrapost-position. Start with the vertical axis first and then the slanting construction lines for hip and shoulders. You can dress up your figure and create an environment for it.
EXTRA: ask a friend to pose for you in a contrapost. Draw your model live or take a photo first to draw the posture afterwards.
The contraposto as a natural basic pose was invented by sculptors in ancient Greece. Stiff and static statues no longer fitted in with the stories in which the Olympian gods behaved like supermen and experienced all kinds of exiting adventures.