Forward up, backflipping on pitch (5)
I believe the answer is:
pushy
'forward' is the definition.
(I've seen this in another clue)
'up backflipping on pitch' is the wordplay.
'backflipping' is a reversal indicator.
'on' is a charade indicator (letters next to each other).
'pitch' becomes 'shy' (I've seen this before).
'up' back-to-front is 'pu'.
'pu'+'shy'='PUSHY'
(Other definitions for pushy that I've seen before include "Informally aggressive, not patient" , "Overly assertive" , "Excessively self-assertive" , "Aggressive; overbearing" , "Forward" .)