Able-Bodied Strength (3.5e Feat)
From D&D Wiki
Able-Bodied Strength [General, Fighter]
Your body has such great endurance and super-humanoid abilities that your strength is greatly increased.
Prerequisite: Defeat a monster with a Large or higher size category, Have at least 1 DR that cannot be bypassed, Str: 20+, Fast Healing 10, Lightning Reflexes, Combat Reflexes
Benefit: Gain Strength equal to 1/2 character level.
Normal: no bonus