I do not want to contradict the research by this, but our heads certainly aren't all too well adapted to punching. The brain is to a large extent floating quite

I do not want to contradict the research by this, but our heads certainly aren't all too well adapted to punching. The brain is to a large extent floating quite freely in the cerebrospinal fluid in the skull, and when the head is punched it experiences an effect similar to a passenger in a suddenly breaking car - it is smashed against the skull as a result of inertia, often resulting in permanent brain trauma: http://en.wikipedia.org/wiki/Dementia_pugilistica http://en.wikipedia.org/wiki/Dementia_pugilistica http://en.wikipedia.org/wiki/Chronic_traumatic_encephalopathy http://en.wikipedia.org/wiki/Chronic_traumatic_encephalopath... In fact, many people die from just a single punch to the head. They become unconscious and fall on the concrete, for example: http://www.smh.com.au/national/90-killed-in-singlepunch-assaults-since-2000-20131201-2yjtr.html http://www.smh.com.au/national/90-killed-in-singlepunch-assa...