physical exercise vs effort

physical exercise and effort both are nouns.

Word	Noun	Adjective	Verb	Adverb
physical exercise	Yes	No	No	No
effort	Yes	No	No	No

As nouns, effort is a hypernym of physical exercise; that is, effort is a word with a broader meaning than physical exercise:

physical exercise: the activity of exerting your muscles in various ways to keep fit
effort: use of physical or mental energy; hard work

Other hypernyms of physical exercise include elbow grease, exertion, sweat, travail.

physical exercise (noun)	effort (noun)
the activity of exerting your muscles in various ways to keep fit	earnest and conscientious activity intended to do or accomplish something
	use of physical or mental energy; hard work
	a notable achievement
	a series of actions advancing a principle or tending toward a particular end