I find waiting for things physically exhausting. Waiting in lines, waiting sitting in a room, waiting on friends to decide what they want to eat, walking really slowly with an elderly relative: I find it all physically exhausting even though very little physical energy is required.
I used to, but I learned to close my eyes and either meditate on my breath, or repeat a mantra in my head.
Now, waiting is an opportunity to calm my mind and quiet my brain.