Back exercises work the lats (latissimus dorsi), the large triangular muscles on either side of the back, as well as the muscles of the middle back and lower back, such as the erector spinæ. Overall the back is one of the most complicated body parts, as it consists of a series of interconnected muscles. Back exercises can be broken down into exercises that target one of four major areas: 1) the upper lats, 2) the lower lats, 3) the middle back, and 4) the lower back. The pull up and reverse pushup are the best bodyweight back exercises.