Muscle of the Month: Latissimus Dorsi
Location: The latissimus dorsi is one of the largest muscles in the back, located in the middle of the back and partially covered by the trapezius.
Attachments (where the muscle starts and ends):
Origin: Spinous processes T7-L5 vertebrae, Iliac Crest of Sacrum. Thoracolumbar Fascia, Inferior Angle of the scapula, Lower 3-4 ribs. Essentially, the muscles begins on the lower part of the spine, upper pelvis, and the lower ribs with an attachment to the scapula as well.
Insertion: Floor of intertubercular groove of the humerus, or the top of the upper arm.
- Adduction of the arm at the shoulder
- Extension of the arm at the shoulder
- Internal rotation of the arm at the shoulder
- Assists with flexion, extension, and lateral flexion of the trunk
- Assists with anterior and lateral pelvic tilt
- Assists with depression and protracton of scapula
- Assists with deep inspiration and forced expiration
Exercises that use this muscle:
- Lat Pulldown
- Straight Arm Pulldown
- Bent-over rows w/underhand grip
- Seated Row
Summary: Latissimus Dorsi Muscle literally means, “broadest muscle of the back”. With that being said, it is one of the widest muscles in the entire body. Although the lats are not used commonly in daily activities, they are generally active in the majority of pulling movements. If you are ever going rock climbing or like to climb ropes, be sure to train your lats!