Your body is powerfully built, whether outright hulking with muscle mass or simply lean and veritably carved from stone. Whether you work out religiously or simply have natural toning that is easily maintained, you are exceptionally dense with raw muscle.
All damage you receive is reduced by STR/3. Further, any critical hits against you have their critical effect reduced by 1 category. So if someone strikes you three times, they only inflict a level 2 critical.