I see a lot of tight latissimus dorsi muscles. The latissimus dorsi is a large broad muscle of the back that connects the arm to the spine (via the thoracic and lumbar vertebra) and pelvis (through the thoracolumbar fascia). The latissimus dorsi, often referred to as the lats, was our swinging from the trees muscle and now is responsible for pulling the arm away from and behind the body as well as rotating the arm towards the midline from the shoulder.
Even though the latissimus dorsi is a back muscle you can often spy a tight latissimus dorsi from looking at the front of the body. If the bones at base of the ribcage are protruding it is a good bet that you have a tight latissimus dorsi. The tight latissimus pulls down at the lower back which in turn pushes the base of the ribcage forward and up.
Good movement patterns are often hindered by tight latissimus dorsi muscles. Every step we take should involve a twist of the spine and tight latissimus dorsi muscles can prevent that from happening.
What I see most often in regards to a tight latissimus dorsi and walking is an upper back that doesn’t move. I spend my days watching articles of clothing making or failing to make wrinkles in fabric as we move.
When the latissimus dorsi is tight the shirt of the person walking will remain static as they walk. With good walking patterns that twist with each step wrinkles in clothing will manifest with every step.
The latissimus dorsi test/stretch in the video above is something I use if nothing else will get movement going in the upper trunk. The body is a self-healing machine if used well and twisting the spine with every step is one of the healthiest aspects of a successful walking pattern.