Endless enthusiasm, etc., swallowing one type of bubbly (9)
I believe the answer is:
energetic
'bubbly' is the definition.
(thesaurus)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for energetic that I've seen before include "Involving great activity" , "It's vital" , "Lively, spirited" , "'Animated, full of life (9)'" , "Full of go" .)