An overworked teres major muscle or one that contains trigger points can mimic shoulder bursitis or a thoracic outlet syndrome.
Common people that suffer are athletes like gymnasts, rock climbers, baseball players or rowers.
Trigger points in your muscles can make them ache right at their location and at other, seemingly unrelated parts of your body.
The main pain zone of the teres major is the back of your shoulder.
Beside that, pain can radiate to the front and side of your shoulder and down the backside of your arm.
This is why it is often involved in
In the pictures below the red colour tells you how common it is to feel an ache in the highlighted area.
The darker the colour, the likelier it is to feel pain in the respective spot when your teres major muscle contains trigger points.
If this muscle is overworked, all movements that require lifting your arm to the side and in front of you may be impaired and/or painful.
Because an overworked muscle usually is very tight and in a shortened position.
The movements mentioned above all include an elongation of the muscle as they display the opposite direction of the muscle functions.
On the other side pulling on things – pulling on a blind to open it – may be also painful because the muscle has to work.
Always remember: An overworked and tender muscle may give you trouble, no matter if you contract and thus “use” it, or if you stretch it.