Not an inspiring thing to do when no longer healthy (6)
I believe the answer is:
exhale
'not an inspiring thing to do' is the definition.
I can't judge whether this defines the answer.
'no longer healthy' is the wordplay.
'no longer' becomes 'ex' (prefix meaning former or onetime).
'healthy' becomes 'hale' (hale can mean fit and healthy).
'ex'+'hale'='EXHALE'
'when' is the link.
Can you help me to learn more?
(Other definitions for exhale that I've seen before include "Puff away" , "Expel air from the lungs" , "let breath out" , "send forth wind" , "Puff perhaps" .)