Start to cover leg and shin up (5)
I believe the answer is:
climb
'shin up' is the definition.
(thesaurus)
'start to cover leg' is the wordplay.
'start to' says to take the initial letters.
'leg' becomes 'limb' (I've seen this before).
The first letter of 'cover' is 'c'.
'c'+'limb'='CLIMB'
'and' is the link.
(Other definitions for climb that I've seen before include "Get a rise" , "Ascend, scale" , "Slope upwards" , "Go higher up" , "Scale or clamber" .)