Don't remember ever feeling like a Gazelle. I am sure there are some who can. I imagine it to be a combination in ebullience that includes clear eyes, a spring in the step and a level of energy those who have never felt like a Gazelle might call an irritating restlessness accompanied by fidgeting and highly imaginative reasons to transcend the physical.
Ebullience comes from the Latin word to bubble. A boiling up that might find release in levels of activity such as running around like a mental patient with a wheel barrow. However I am able to say that the compost piles are pretty much moved, and I believe I have always known what it feels like to be a Gazelle run over by a steam roller.