Take a very wide stance and flare the feet, placing the arms in the mummy position across the upper body. Most people will gravitate toward a 45-degree flare but some prefer a straighter foot angle, depending on their hip anatomy.
Squat by sitting back, keeping the trunk upright and knees force outward throughout the movement.
Descend until the thighs are parallel to the ground, Rise to a standing position.
Primary: Quadriceps (rectus femoris, vastus lateralis, vastus medialis, vastus intermedius)
Secondary: Gluteus maximus, gluteus medius, gluteus minimus, hamstrings (biceps femoris, semitendinousus, semimembranosus), adductor magnus, adductor longus, adductor brevis.
Erector spinae (spinalis, longissimus, iliocostalis), deep-hip external rotators.