Finalists in foot race warm up to pace (5)
I believe the answer is:
tempo
'pace' is the definition.
(I know that pace can be written as tempo)
'finalists in foot race warm up to' is the wordplay.
'finalists in' says to take the final letters.
The final letters of 'foot race warm up to' are 'TEMPO'.
(Other definitions for tempo that I've seen before include "Cadence" , "Beat (music)" , "Muscial time" , "Speed of 3A" , "Metronome output" .)