Hi Rebekah 🙂
Thanks for the great questions! While it does seem odd that yawning is normal during exercise, it IS! This is actually a conditioned response from your body and your brains way of ‘cooling’ down your body in a sense. It increases the amount of blood that travels to your brain and inevitably lowers the temp of that blood.
As your body heats up, your brain combats it by yawning. Like a natural built in AC unit, heehee!
Hope this helps.
Hugs!
