Running smart (7)
I believe the answer is:
dashing
I believe this clue is a double definition.
'running' is the first definition.
(dashing is a kind of running)
'smart' is the second definition.
(thesaurus)
(Other definitions for dashing that I've seen before include "sprinting" , "Rakish" , "as blade might be" , "Making haste" , "Frustrating; debonair" .)