It also uses your hip flexors (muscles on your upper thighs below your hip bones). Mastering Crunches Keep your neck in line with your spine. Tuck in your chin so it doesn't stick out. Breathe normally. To keep chest and shoulders open, keep your elbows out of your line of vision. ...
the support1000may flex, rotate, or otherwise move in a plane that is generally parallel with a front face of the support1000. For example, as the support1000rotates in this plane, the teeth1020may move closer together through the voids1030, creating a curvature or flexion motion in that pl...
the support1000may flex, rotate, or otherwise move in a plane that is generally parallel with a front face of the support1000. For example, as the support1000rotates in this plane, the teeth1020may move closer together through the voids1030, creating a curvature or flexion motion in that pl...