Put on a dip belt. Attach the strap/chain to the cable's carabiner.
Take a few steps back. Begin to squat by flexing at the knees and hips.
Let the weight pull you forward as you squat. Then push your toes through the front of your shoes as you squat back to the start position.
Cable Belt Squat 运动指南 - Quads 锻炼 | MuscleWiki