Passion reportedly more exhausting in EastEnders (6)
I believe the answer is:
ardour
'passion' is the definition.
(I know that ardour is a type of passion)
'reportedly more exhausting in eastenders' is the wordplay.
'reportedly' indicates a 'sounds like' (homophone) clue.
'more exhausting in eastenders' becomes 'arder' (Cockney pronunciation of 'harder').
'arder' is a homophone of 'ARDOUR'.
(Other definitions for ardour that I've seen before include "Fervour, zeal" , "Warm, passionate feeling" , "Fervency" , "Great warmth of feeling or love" , "Enthusiasm or warmth of passion" .)