Live sex could result in this hit (8)
I believe the answer is:
belabour
'result in this hit' is the definition.
'belabour' can be an answer for 'hit' (I've seen this before). I'm not certain of the 'result in this' bit.
'live sex' is the wordplay.
'live' becomes 'be' (synonyms).
'sex' becomes 'labour' (I am not sure about this - if you are sure you should believe this answer much more).
'be'+'labour'='BELABOUR'
'could' is the link.
Can you help me to learn more?
(Other definitions for belabour that I've seen before include "Harangue" , "Attack with blows or words" , "Attack physically or verbally" , "censure" , "criticize" .)