Go out of shape, practically (3)
I believe the answer is:
pep
'go' is the definition.
(I've seen this before)
'out of shape practically' is the wordplay.
'out of' indicates a hidden word.
'PEP' can be found hidden inside 'shape practically'.
(Other definitions for pep that I've seen before include "Energy, zip" , "Go" , "Energy, liveliness" , "Palindrome for vigour" , "Energy or enthusiasm" .)