The middle deltoid is stretched with adduction of the arm at the shoulder (glenohumeral) joint (in extension behind the back).
Note: This stretching protocol is likely to stretch the coracobrachialis as well.
![The middle deltoid is stretched with adduction of the arm at the shoulder joint (in extension behind the back).](https://learnmuscles.com/wp-content/uploads/2017/10/Middle-deltoid-stretch-528x1024.jpg)
The middle deltoid is stretched with adduction of the arm at the shoulder joint (in extension behind the back).