Mabel changes to a leisurely pace (5)
I believe the answer is:
amble
'a leisurely pace' is the definition.
(I've seen this in another clue)
'mabel changes' is the wordplay.
'changes' indicates anagramming the letters.
'mabel' is an anagram of 'AMBLE'.
'to' acts as a link.
(Other definitions for amble that I've seen before include "Blame (anag.)" , "Go at a leisurely gait" , "Wander gently along" , "promenade" , "Meander" .)