Relaxed about exercise, Charlie appreciated (9)
I believe the answer is:
respected
'appreciated' is the definition.
(thesaurus)
'relaxed about exercise charlie' is the wordplay.
'relaxed' becomes 'rested' (I've seen this before**).
'about' indicates putting letters inside.
'exercise' becomes 'pe' (Physical Education).
'charlie' becomes 'c' (phonetic alphabet: alpha, bravo, charlie etc.).
'pe'+'c'='pec'
'rested' going around 'pec' is 'RESPECTED'.
(Other definitions for respected that I've seen before include "Held in high regard" , "Held in esteem" , "Looked up to" , "Regarded highly" , "'Esteemed, showed deference to (9)'" .)