What is lat insertions?

Latissimus dorsi (lats) is a large muscle group in the back that is responsible for shoulder extension, adduction, and internal rotation. The lats originate from the spine, the lower six thoracic vertebrae, the lumbar vertebrae, and the back of the iliac crest. They insert into the humerus bone of the upper arm.

The latissimus dorsi has two insertions: the most common is the humeral insertion, which comes from the intertubercular groove of the humerus bone. The lesser-known insertion is the iliac crest, which originates from the anterior part of the iliac crest, the part of the pelvis where the hip bones meet.

The humeral insertion is the larger of the two, and it is responsible for most of the movement of the lats. The iliac crest insertion is smaller and assists in stabilizing the pelvis during certain movements, particularly during rowing exercises.

It's important to train both insertions of the lats to ensure they function optimally and to avoid muscle imbalance, which can lead to injury and reduced performance. Exercises that target the humeral insertion include pull-ups, lat pull-downs, and rows. For the iliac crest insertion, exercises like side planks, deadlift, and twisting movements like Russian twists can help.