Religious leader has exercises about work (4)
I believe the answer is:
pope
'religious leader' is the definition.
(I've seen this in another clue)
'exercises about work' is the wordplay.
'exercises' becomes 'pe' (Physical Education class).
'about' says to put letters next to each other.
'work' becomes 'po' (I can't explain this - if you can you should believe this answer much more).
'pe' put after 'po' is 'POPE'.
'has' is the link.
Can you help me to learn more?
(Other definitions for pope that I've seen before include "man of great authority" , "freshwater fish" , "Francis < Alexander" , "fisherman's successor" , "Holy man" .)