How does a person stay balanced while leaning over a moving snowboard?

[Minhtran1092]

I started snowboarding a year ago and while watching a Ryan Knapton tutorial video on how to carve (riding on the edge of a snowboard), I noticed he didn't tip over and fall onto the snow even when he leans over his board to a great degree. There are two types of turn maneuver one can do on a snowboard: toe-side turns (leaning forward) and heel-side turns (leaning backwards):

If he wasn't moving, he'd certainly fall over. I'm curious about the dynamics that's keeping him balanced throughout the turn. In case it's relevant, 'carving' refers to riding on the *edges* of one's snowboard, following an S-curve path down the slope of a mountain.

 

[Lnewqban]

He is describing a curvilinear trajectory, leaning his body towards the center of the curve in order to compensate for the forces of turning:

 

[jedishrfu]

Here's a video on how cars bank on a turn which is a similar phenomena: