Latissimus Dorsi

The Latissimus dorsi muscle is one of the largest in the body. It is a powerful extensor muscle of the arm and is used extensively in chinning and climbing. They are commonly known at the lats.

Origin

• Posterior crest of the ilium (via the Thoracolumbar fascia)
  
  
• Posterior sacrum
  
  
• Spinous processes of T7-L5

Insertion

• Intertubercular groove (between the greater and lesser tuberosities) of the humerus

Actions

• Extension
  
  
• Internal rotation
  
  
• Adduction

Innervation

• Thoracodorsal nerve

Daily uses

• Pushing on the arms of a chair when standing up

Example strengthening exercises

• Lat pull down using a resistance band

Example stretches

• Latissimus dorsi stretch I
  
  
• Latissimus dorsi stretch II

Related injuries

• Tight muscles in the upper back and neck

Related muscles

• Teres major