This topic has 2 voices and 1 reply. Viewing 2 posts - 1 through 2 (of 2 total) Author Posts November 9, 2014 at 7:26 pm #11815 Brian TimlinParticipant Just wondering what carbs are used during HIIT and LSD cardio?Is it from the liver, muscles or both?Also do different types of HIIT use different fuel sources because obviously we have 10 second all the way up to 4 min intervals in HIIT. November 9, 2014 at 7:52 pm #227263 Trevor G FullbrightModerator It will take it from both.Though LSD also largely will oxidize fat for fuel. Author Posts Viewing 2 posts - 1 through 2 (of 2 total) You must be logged in to reply to this topic.