We could also compare this defensiveness of humans to animals. Animals also have their own ways to protect themselves. A good example is the chameleon that tends to use camouflage as its defensive mechanism.
If a person would want to attack another person the first thing the person being attacked would do is protect their face, vital organs, fend off (with arms held out). Using any physical object might be of great use to defend yourself too although this object can be small as a tennis ball or as big as a chair. You feel that you have power over this barrier and that it comforts you in a way of feeling safe. Many children also tend to hold animals or objects close to them all the time - whether it's close to their chest or they hide behind it because they feel vulnerable but they feel as if the objects keep them safe.
Further we look at pre-empting attack whether you give in or attack first. Signals giving this away is avoiding to look at the other person, keeping your head down, crouching and when attacking first the body could be erect and thrust forward.
Attack and defense both appear together therefor the body language might become confusing. The upper body may be showings signs of attack whilst the legs are twisted together communicating defensiveness.
