Outstrip when restored to health (6)

I believe the answer is:

better

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'outstrip' is the definition.
(bettering is a kind of outstriping)

I can't explain the remainder of the clue.

(Other definitions for better that I've seen before include "no longer sick" , "Superior; gambler" , "Gambler; more effective" , "Preferable" , "More desirable; gambler" .)

I've seen this clue in the Evening Standard.

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