It isn't unusual to have a better understanding of your arm muscles, because you can see them all the time, but they are not the prime movers. What muscles do close grip pull ups work? How To Do 20 Pullups In One Set Athlean-x Bodyweight Back Workout Back Workout Lower Back Exercises Both exercises will primarily train your back, lats and biceps, however, there are some slight differences in the degree in which those muscles get worked. What muscles does pull ups work . One arm pullup is more difficult. However, they do also work other muscles such as the teres major, brachioradialis, brachialis, triceps, levator scapulae, rotator cuff, erector spinae and the obliques. The big back muscles are called latissimus dorsi and rhomboids. Pull ups are a great exercise to strengthen and tone your upper body. Obviously because normal chinups are lot. The form of a pullup is easy to remember and simple to perform, so long as you have a sufficient foundation of strength to lift y...