Toe walking

From ActuallyAutistic Wiki

Toe walking means walking on the balls of your feet, with your heels raised off the ground. Despite the name, it does not require being all the way up on your toes or possibly on pointe, like a ballerina. Toe walking can be a stim or just a more comfortable way to walk. It can be quieter than using your full foot and give your body more proprioceptive information.