A limit on exercise - all wrong, unaccompanied (9)

I believe the answer is:

acappella

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'a limit on exercise all wrong unaccompanied' is the definition.
I can't judge whether this definition defines the answer.

'a limit on exercise all wrong' is the wordplay.
'limit' becomes 'cap' (capping is a kind of limiting).
'on' is an insertion indicator (as in clothing 'on' a person).
'exercise' becomes 'pe' (Physical Education).
'wrong' indicates anagramming the letters.
'all' with letters rearranged gives 'lla'.
'pe' inserted inside 'lla' is 'pella'.
'a'+'cap'+'pella'='ACAPPELLA'

Can you help me to learn more?

(Another definition for acappella that I've seen is " sung without accompaniment".)

I've seen this clue in The Daily Express.

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