How to Build the “Inner” & “Outer” Lats

Did you know that the latissimus dorsi (aka the “lats”) is the widest muscle in the human body?? It is absolutely massive, and spreads across most of your back. Yet, like with other muscles, the vast majority of people treat it as one single muscle region. If you’ve followed me for any length of time, you know that’s not the case! Region-specific activation and nonhomogeneous hypertrophy principles come into play to determine which regions of any given muscle fiber are worked the most, and no exercise exists that will work every region of a muscle perfectly equally.

Due to the wide variety and spread of the latissimus dorsi’s origination points  (see Image 1 below),  it’s regional hypertrophy is even more pronounced than with most muscles. In fact, research has shown that it can be functionally divided into two separate regions – medial (aka “inner lats”) and lateral (aka “outer lats”). and that it’s much easier to work the inner than the outer region! (See Image 2 below)

Here’s the key. Exercises that focus on shoulder extension, shoulder adduction or shoulder internal rotation all work the inner lats more than the outer. While only exercises that focus on shoulder depression work the outer region more than the inner! (Movement examples available on my website via those hyperlinks – they’re all on the same page)

APPLICATION: If you want to “widen” your back by building the “outer” lats, use exercises that apply shoulder depression! And if you want to build your middle back via your lats, use exercises that apply shoulder extension, adduction, or internal rotation!

Note: Dozens of exercises accurately and effectively applying all the above movements can be found in the Back Content section of the All-Access Basic Membership, and are synthesized into a comprehensive science-based workout routine in the Hypertrophy Series Total Back Program!

Relevant Research Article(s):
      1) Differential activation of parts of the latissimus dorsi with various isometric shoulder exercises

Related Dr. Gains YouTube Video(s):   
      1) Hit EVERY BACK MUSCLE in ONE COMBO EXERCISE!! (Plus “Fast-Twitch“ Finisher) – Using Any Free Weight!