A large and powerful muscle that covers the lower part of the back above the hip bones and extends up to the outside front of the arm bone. It allows us to pull ourselves up by the arms, like climbing a ladder or pull things down and back like when paddling a canoe or swimming. It also helps bring our arm closer to our side, turn it inwards, and move it backwards.
When there is trouble with this muscle, we may feel pain around the bottom of the shoulder blade, on the back of our armpit and down the back of the arm to the last two fingers or on the side at the waist. Your massage therapist may treat this muscle when you are lying on your stomach or on your side and may use deep stripping and/or pincer compression to increase the blood flow and release any tension or trigger points in the area.
To stretch this muscle, simply raise your arms above your head and hold for 10 to 15 seconds. Alternatively, cross your wrists and hold on to a door knob (or the like) then lean back.