second wind vs energy

second wind and energy both are nouns.

Word	Noun	Adjective	Verb	Adverb
second wind	Yes	No	No	No
energy	Yes	No	No	No

As nouns, energy is a hypernym of second wind; that is, energy is a word with a broader meaning than second wind:

Other hypernyms of second wind include get-up-and-go, push.

second wind (noun)	energy (noun)
the return of relatively easy breathing after initial exhaustion during continuous exertion	forceful exertion
renewed energy or strength to continue an undertaking	an imaginative lively style (especially style of writing)
	enterprising or ambitious drive
	(physics) a thermodynamic quantity equivalent to the capacity of a physical system to do work; the units of energy are joules or ergs
	any source of usable power
	a healthy capacity for vigorous activity