Poised to explode with energy to get fit (7)
I believe the answer is:
episode
'fit' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Maybe there's a link between them I don't understand?
'poised to explode with energy' is the wordplay.
'to explode with' indicates anagramming the letters.
'energy' becomes 'e' (physics symbol as in E=mc2).
'poised' anagrammed with 'e' makes 'EPISODE'.
'to get' is the link.
Can you help me to learn more?
(Other definitions for episode that I've seen before include "Chapter or event" , "Instalment of broadcast serial" , "Incident forming part of a sequence" , "Incident or one part of a story" , "Distinctive incident" .)