What’s initially curtailing run after muscle pain? (5)
I believe the answer is:
cramp
'muscle pain?' is the definition.
(I've seen this in another clue)
'what's initially curtailing run after' is the wordplay.
'what's initially' suggests taking the first letters.
'run' becomes 'ramp' (I can't justify this - if you can you should believe this answer much more).
'after' means one lot of letters go next to another.
The initial letter of 'curtailing' is 'c'.
'c'+'ramp'='CRAMP'
Can you help me to learn more?
(Other definitions for cramp that I've seen before include "development of vice" , "Confine - muscular spasm" , "To restrict; a muscle pain" , "Painful muscular contraction" , "Contract" .)