If you’ve ever rowed a boat, done a pull-up, or deadlifted weight, you’ve probably felt the effects in your lats. Your Latissimus dorsi (lats) are the broadest of the main muscles in your back and are located in your mid/lower back.
The muscle is responsible for extension (rowing, swinging your arms as you walk), adduction (pull-ups, chin-ups, or lifting a heavy object from a shelf above your head) and rotates the arm toward the body’s midline (like when you fold your arms over your chest) and serves a minor role in assisting other muscles.
While your lats perform important functions, they also are largely responsible for holding the shape and contours of your midsection and chest. Developed lats make for a trimmer appearance.
For those into anatomy, here’s the official scoop on the lats:
Muscle: Latissimus dorsi (Musculus latissimus dorsi)
Attachments:Origin: (proximal attachment)a. Spinous processes of T7 – L5 vertebrae.b. Iliac crest of sacrum.c. Thoracolumbar fascia.d. Inferior angle of the scapula.e. Lower three or four ribs.Insertion: (distal attachment)a. Floor of intertubercular (bicipital) groove of humerus.
Actions:a. Adducts the arm at the shoulder (glenohumeral) joint.b. Medially rotates the arm at the shoulder (glenohumeral) joint.c. Extends the arm at the shoulder (glenohumeral) joint.
Care and feeding of the lats
Like any other muscle, proper diet, nutrition and targeted exercise are key to healthy development. Specific exercises, like lat pulls, rowing, pull-ups (wide, narrow, kipping), and bent-arm barbell pullovers, work to broaden and lengthen the muscle. It’s also important to balance your workouts to develop the antagonist (opposite) muscles to ensure a natural appearance. In the case of your lats, working your deltoids is an effective shape-balancing trick. Working the lat’s synergist muscles (helpers) like the rhomboids, traps and levator scapulae are also a good idea.
If you sit a lot at work, your lats can suffer. Watch your posture when seated and take frequent breaks to walk around your office. Massage can work too. A good massage therapist can spend 10 or so minutes doing point work and cross-fiber massage and make a huge difference in the recovery of an overworked muscle. They can help sore lats, too.