Lacking inspiration he goes for a walk (10)
I believe the answer is:
pedestrian
This clue is a double definition.
'lacking inspiration' is the first definition.
(I've seen this before)
'he goes for a walk' is the second definition.
(I've seen this before)
(Other definitions for pedestrian that I've seen before include "Unexciting" , "A person travelling on foot" , "flat" , "lame" , "Boring" .)