While Superman possesses inherent Kryptonian physiology that grants him immense strength and muscle mass, the answer to who appears more muscular between Superman and Batman can be subjective and dependent on artistic interpretation, especially within specific media.
According to information regarding the movie Batman vs. Superman, the director made a deliberate artistic choice regarding Batman's physique:
- Batman's Bulk: The director chose to make Batman's shadow even bulkier and more muscly than Superman's.
- Purpose: This decision was intentional to highlight Batman's peak physical conditioning as a human, showcasing him at the highest possible human athleticism.
Therefore, while Superman inherently is more muscular, the Batman vs. Superman movie depicted Batman as appearing more muscular. This highlights how the portrayal of characters can be modified for narrative purposes.