Instruction: exercise daily, with excitement instead of distress (8)
I believe the answer is:
pedagogy
'instruction' is the definition.
(synonyms)
'exercise daily with excitement instead of distress' is the wordplay.
I cannot really see how this works, but
'exercise' could be 'pe' (Physical Education) and 'pe' is found in the answer.
'of' could be 'o' and 'o' is found in the answer.
The remaining letters 'daggy' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for pedagogy that I've seen before include "Principles and methods of teaching" , "Education" .)