Fit crooner protecting energy and good health (9)

I believe the answer is:

wellbeing

I'm a little stuck... Click here to teach me more about this clue!

'good health' is the definition.
'wellbeing' can be an answer for 'health' (I've seen this before). I am unsure of the 'good' bit.

'fit crooner protecting energy' is the wordplay.
'fit' becomes 'well' (associated in meaning).
'crooner' becomes 'Bing' (Bing Crosby).
'protecting' is an insertion indicator (inserted letters are held or protected).
'energy' becomes 'e' (physics symbol as in E=mc2).
'bing' enclosing 'e' is 'being'.
'well'+'being'='WELLBEING'

'and' acts as a link.

Can you help me to learn more?

(Other definitions for wellbeing that I've seen before include "good shape" , "Contentment and good health" .)

I've seen this clue in The Times.

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