China perhaps includes one form of exercise (7)
I believe the answer is:
pilates
'form of exercise' is the definition.
(I've seen this before)
'china perhaps includes one' is the wordplay.
'china perhaps' becomes 'plates' (I've seen this in another clue).
'includes' indicates putting letters inside.
'one' becomes 'i' (Roman numeral).
'plates' placed around 'i' is 'PILATES'.
(Other definitions for pilates that I've seen before include "discipline?" , "attributed to Biblical procurator?" , "Modern exercise" , "Holistic system of physical exercises" , "Pleats I arrange into a form of exercise" .)