a gut reaction
COMMON A gut reaction is a reaction that you have immediately and strongly, without thinking about something or being aware of your reasons. At first my gut reaction was to never write again. My heart's loyal to the party but my gut reaction is to vote against the bill.
1. If you describe a task or activity as gut-busting, you mean it is very hard work. It would be hard work, he predicted — back-breaking, gut-busting, unbelievably hard work.
2. You can use gut-busting to describe a very large amount of food. Walker set a record by eating a gut-busting 32 pies.