Is it normal to shake when you yawn?
Mostly.Normal for most people
Yes, a brief shiver or shake during a yawn is usually harmless. Yawning stretches a lot of muscles at once, and your body can respond with a little tremble.
A yawn isn’t just a big inhale—it often comes with a full-body stretch, which can make your muscles briefly quiver or give you a shivery feeling. Lots of people notice it now and then.