Sprinted back at speed to tell (7)
I believe the answer is:
narrate
'tell' is the definition.
(I know that tell can be written as narrate)
'sprinted back at speed' is the wordplay.
'sprinted' becomes 'ran' (I've seen this in another clue).
'back' is a reversal indicator.
'at' is a charade indicator (letters next to each other).
'speed' becomes 'rate' (both can mean pace).
'ran' back-to-front is 'nar'.
'nar'+'rate'='NARRATE'
'to' is the link.
(Other definitions for narrate that I've seen before include "Read" , "Tell us the story" , "recount events" , "Tell story,recount" , "Relate events" .)