panting vs heaving

panting and heaving both are nouns.

Word	Noun	Adjective	Verb	Adverb
panting	Yes	No	No	No
heaving	Yes	No	No	No

As nouns, panting and heaving are synonyms defined as:

panting (noun)	heaving (noun)
breathing heavily (as after exertion)	throwing something heavy (with great effort)
any fabric used to make trousers	breathing heavily (as after exertion)
	the act of lifting something with great effort
	an upward movement (especially a rhythmical rising and falling)