Muscular men mostly backed fee being revised (8)
I believe the answer is:
beefcake
'muscular men' is the definition.
(I've seen this before)
'mostly backed fee being revised' is the wordplay.
'mostly' means to remove the last letter.
'being revised' indicates an anagram.
'backed' with its last letter taken off is 'backe'.
'backe'+'fee'='backefee'
'backefee' is an anagram of 'BEEFCAKE'.
(Other definitions for beefcake that I've seen before include "Certain photos" , "Men displaying muscles" , "Displayed male muscles" , "Photo of a muscular man with not much on" , "musclemen" .)