Anyone watching former Vice President Joe Biden in the moments before Thursday night’s Democrat primary debate might be surprised to watch his physical behavior prior to his big moment.

Biden’s bizarre pre-debate ritual was revealed by former Alaska Governor Sarah Palin after she debated the former Vice President in the 2008 debates.

Palin detailed her experience in her best-selling book Going Rogue.

Finally Biden appeared, as usual looking impeccable in his dark suit, tall and confident, his distinguished silver hair flawlessly groomed. I had never met him before, but now I tried to catch his eye, to give him, I don’t know, a friendly nod, a thumbs-up, something to acknowledge that, hey, ultimately we’re all on the same team. Go, U.S.A.! But Senator Biden didn’t make eye contact. Instead he looked past me. His features then hardened into what can only be described as a ‘game face.’ I could respect that. I knew what it was like to get into a zone before a big game. Then the senator started to stretch. Literally. He put his hands on his hips and, staring grimly at some point behind me, began to bend at the waist, bouncing first to the right, then to the left. Then the neck rolls started, presumably to get rid of all that nasty tension from being the front-runner. After that, the senator from Delaware began stretching his quads, grabbing his dress shoe and pulling it up behind his designer-suited rear end. Right leg, then left. I’m thinking, O-kay. Didn’t know this was going to get physical.

It is unclear whether Biden employed this ritual only while debating Palin or whether it’s something he does every time his debates. The former vice president and senator has decades of experience on the debate stage, although he has never been the front-runner in a Democrat primary.

Biden faces nine of his 2020 rivals for the Democrat nomination for president on Thursday night’s debate on MSNBC.