When massaged, a toned leg stretched (9)
I believe the answer is:
elongated
'stretched' is the definition.
('elongate' can be a synonym of 'stretch')
'when massaged a toned leg' is the wordplay.
'when massaged' is an anagram indicator.
'a'+'toned'+'leg'='atonedleg'
'atonedleg' is an anagram of 'ELONGATED'.
(Other definitions for elongated that I've seen before include "going further" , "Go al dente to be lengthened or prolonged" , "Stretched" , "Dangle toe (anag)" , "Put on stretcher" .)