Sarcastic Anatomy – Latissimus Dorsi

Scrabble score – 18 points.  Super weak for 15 tiles (and assuming spaced words are even legit in Scrabble).

Plural – generally the lats are referred to as a singular muscle group and dorsi is already plural, but how cool would it be to say “latissimuses” more often. Hippopotamuses do it.

Latin origin – The name Latissimus dorsi sounds like either a Harry Potter villain or one of the dinosaurs that didn’t make it off the island in the last Jurassic Park movie – but the derivation literally means “broadest” “dorsal”.  And stolidus means "stupid", which is what I think about this name.  I know Latin is the scholarly language, but they’re losing major creativity points in my book.

The gist –  In PT school, it didn’t take long to realize Lat is a greedy a$$hat. Not only does it attach everywhere (thoracic spine, lumbar spine, sacrum, iliac crest, ribs, humerus and sometimes the scapula) – but it is innervated by the cervical spine (C6-8) and has its very own peripheral nerve (Thoracodorsal).  Lat attaches to the floor of the bicipital groove, well-shielded in this rough neighborhood by his other internally-rotating cronies – pec major and teres major.  Way more protection than necessary against the rival gang of external-rotation in supraspinatus, infraspinatus, and teres minor.

From this humeral attachment, lat flamboyantly slings inferior to the thoracolumbar fascia and distal attachments, literally connecting the humerus to your glutes.

Function – Seriously, lat is responsible for extension, adduction, internal rotation, flexion (from an extended position), and horizontal abduction of the shoulder.  “Wait – so you’re saying lat both flexes AND extends…adducts AND abducts?”  Yep, clearly this honey badger don’t care to seemingly contradict itself.

I haven’t even mentioned that lat helps sidebend + extend the trunk, is one of the en vogue accessory stability muscles of the thorax, can help you breathe (really deep and creepy-like), and in some mammals…fly.

Some of you are thinking the lats sound pretty BA, huh? Well, with great power comes great responsibility.  And let’s just say in most people latissimus dorsi has the responsible attitude of a high school dropout.  Not like drinking Smirnoff Ices at a basement party with limited parental supervision, but more in the context of often being undertrained, weak, and posturally-compromised leading to pain, restriction, or altered movement patterns.  Can’t do a pull-up, perform a proper overhead squat, or pull (…like anything, any type of pulling)? – it’s probably lat’s fault.

Beyond that, lat weakness/dysfunction can mean movement disorder from head to toe with anything involving the hips, trunk, shoulder or upper extremity. And if back pain, thorax pain, shoulder pain, global movement restriction, or breathing weird isn’t bad enough – lat can make your fingers tingle.  Easily turning it into one of the most annoying housewives of the posterior kinetic chain. #haterinthehouse

Training – So let’s train up lats.

Probably the easiest recommendation to make is to generate some lat activation focus in your full body training, making almost any exercise a lat exercise. Easy enough, right?

But if you’re looking to more specifically strengthen lat and doing a pull-up is out of the equation – allow me to make a few recommendations.

#1 Seated row 

Really any kind of row.  Standing, seated, barbell, dumbbell, cable, band resistance.  Seated rows are probably the easiest place to start, but vary the resistance and play around with grip width on the cables to yolk those bad boys.  And when I say row, I don’t mean the rowing machine.

#2 Deadlift

Proper mechanics are key here for both lat and global benefit, and so you don’t completely destroy your back.  Check yourself, before you wreck yourself…and it’s OK to start light.

#3 Lat pulldown

The name gives it away, this exercise is built specifically for the lat-biased bro.  Although I usually recommend more “functional” movement patterns vs machine work – but if you are looking to build some lat strength from square 1, having the ability to start with lighter resistance is an obvious benefit.  If you’ve never used the pulldown machine, pretty much do the exact opposite of this guy…

 

And if none of that helps you, I’m not sure what else to say.  Just kidding.  I’d recommend consulting with a fitness professional if you are completely lost in the gym setting, otherwise if you think lat may or may not be contributing to your issues – consult a physical therapist.  If nothing else, reading this piece either made you acutely aware of your substantial posterior deficiencies, and/or villianized one of the most important muscles in your body.  Either way, my work here is done.

Paul Killoren PT, DPT