Joint musical requires a lot of effort (11)

I believe the answer is:

elbowgrease

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'a lot of effort' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'joint musical' is the wordplay.
'joint' becomes 'elbow joint' (joint of the body).
'musical' becomes 'grease' (Grease is a film musical).
'elbow'+'grease'='ELBOWGREASE'

'requires' acts as a link.

Can you help me to learn more?

I've seen this clue in The Daily Express.

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