quake in one's boots
to be afraid, to shake from fear
I was quaking in my boots when my boss told me to come to his office.
Indoor Short Track and TT Racing
Indoor races consist of either a polished concrete floor with coke syrup or other media sprayed or mopped onto the concrete for traction for the tyres of the motorcycles, or on dirt that has been moistened and hard packed, or left loose (often called a cushion). Similar to size of the Arenacross Arenas or sometimes smaller the riders must have accurate throttle control to negotiate these tight Indoor Race Tracks.
In the U.S., Short Track and TT events are more commonly held outdoors. A Short Track event is one involving a track of less than 1