speed up vs intensify

speed up and intensify both are verbs.

Word	Noun	Adjective	Verb	Adverb
speed up	No	No	Yes	No
intensify	No	No	Yes	No

As verbs, intensify is a hypernym of speed up; that is, intensify is a word with a broader meaning than speed up:

Other hypernyms of speed up include deepen.

speed up (verb)	intensify (verb)
move faster	become more intense
cause to move faster	make more intense, stronger, or more marked
	increase in extent or intensity
	make the chemically affected part of (a negative) denser or more opaque in order produce a stronger contrast between light and dark