This lunge has been referred to as the World's Greatest Stretch. A deep lunge stretches your hip flexors, glutes, quadriceps, and inner thigh muscles. With the thoracic (upper body) rotation, it also stretches your lats, psoas, ribs, pecs, back, and obliques.

Along with stretching, this pose also strengthens the muscles of your core-- the rectus abdominus, the transverse abdominus, and the multifidus--and the shoulder stabilizing muscles such as the rotator cuff and the deltoid.

That's a lot of benefit in one exercise!