muscleman vs doer

muscleman and doer both are nouns.

Word	Noun	Adjective	Verb	Adverb
muscleman	Yes	No	No	No
doer	Yes	No	No	No

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

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

Other hypernyms of muscleman include actor, worker.

muscleman (noun)	doer (noun)
a bully employed as a thug or bodyguard	a person who acts and gets things done
someone who does special exercises to develop a brawny musculature