heartiness vs vigor

heartiness and vigor both are nouns.

Word	Noun	Adjective	Verb	Adverb
heartiness	Yes	No	No	No
vigor	Yes	No	No	No

As nouns, heartiness and vigor are synonyms defined as:

Other synonyms of heartiness include dynamism, vigour.

heartiness (noun)	vigor (noun)
the quality of hearty sincerity	active strength of body or mind
active strength of body or mind	an imaginative lively style (especially style of writing)
	forceful exertion