Wonderbra so fabulous for one heading downhill fast? (11)

I believe the answer is:

snowboarder

'one heading downhill fast?' is the definition.
(a snowboarder might snowboard down a hill)

'wonderbra so fabulous' is the wordplay.
'fabulous' indicates an anagram (a dramatic or fabulous change to the letters).
'wonderbra'+'so'='wonderbraso'
'wonderbraso' with letters rearranged gives 'SNOWBOARDER'.

'for' acts as a link.

(Another definition for snowboarder that I've seen is " One sliding downhill".)

I've seen this clue in The Times.

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