Endure with less energy (7)
I believe the answer is:
undergo
'endure' is the definition.
(I know that endure is a kind of experience)
'with less energy' is the wordplay.
'with' says to put letters next to each other.
'less' becomes 'under' (I've seen this in other clues).
'energy' becomes 'go' (go can mean energy or enthusiasm).
'under' next to 'go' is 'UNDERGO'.
(Other definitions for undergo that I've seen before include "Withstand" , "Suffer, endure" , "Experience or live through" , "Submit to an experience" , "Endure or be subjected to" .)