Continuous exercise almost causes stroke (7)
I believe the answer is:
solidus
'stroke' is the definition.
(I know that stroke can be written as solidus)
'continuous exercise almost' is the wordplay.
'continuous' becomes 'solid' (synonyms).
'exercise almost' becomes 'us' (I am not sure about this - if you are sure you should believe this answer much more).
'solid'+'us'='SOLIDUS'
'causes' acts as a link.
Can you help me to learn more?
(Other definitions for solidus that I've seen before include "Slash symbol" , "Oblique stroke, slash" , "old coin" .)