Race pace (4)
I believe the answer is:
trot
'race pace' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for trot that I've seen before include "moderate movement" , "Run with short steps" , "movement of H [TROT]" , "Go or walk briskly" , "Gait between a walk and a canter" .)