Cried over exercise, putting on weight (4)
I believe the answer is:
wept
'cried' is the definition.
('weep' can be a synonym of 'cry')
'over exercise putting on weight' is the wordplay.
'over' says the letters should be written backwards.
'exercise' becomes 'pe' (Physical Education).
'putting on' is an insertion indicator (some letters wear or 'put on' others).
'weight' becomes 'wt'.
'pe' reversed gives 'ep'.
'ep' going within 'wt' is 'WEPT'.
(Other definitions for wept that I've seen before include "Exclude, prohibit" , ""Jesus __" (shortest verse in the King James Bible)" , "Sobbed heavily" , "lamented" , "Shed tears of grief" .)