muscle-builder vs doer

muscle-builder and doer both are nouns.

Word	Noun	Adjective	Verb	Adverb
muscle-builder	Yes	No	No	No
doer	Yes	No	No	No

As nouns, doer is a hypernym of muscle-builder; that is, doer is a word with a broader meaning than muscle-builder:

muscle-builder: someone who does special exercises to develop a brawny musculature
doer: a person who acts and gets things done

Other hypernyms of muscle-builder include actor, worker.

muscle-builder (noun)	doer (noun)
someone who does special exercises to develop a brawny musculature	a person who acts and gets things done