Horizontal adduction and internal rotation of the humerus are two of the primary functions of the pectoralis major muscle. To stretch this muscle, you would do the opposite actions and hold the end range as demonstrated in the video below.

This particular stretch done in a power rack is far more effective than the typical corner or doorway stretch. The key difference is the barbell – it’s there for a reason! By placing the thighs against the bar, it helps to deload and stabilize the body allowing you to relax further, which will heighten the stretch. The bar also allows you to pivot from the hips, which promotes more external rotation around the shoulder. It doesn’t look like much, but try it and you’ll feel the difference.

Focus on your breathing during the stretch by exhaling longer than you inhale. Exhalation is associated with relaxation – every time you exhale you’ll notice that you’ll go deeper into the stretch.

Hold the stretch for a good 15 seconds then ease out. Do multiple sets in this manner. You can sequence the stretch before back exercises like rows and chins or before doing behind the neck presses or back squats (the stretch will help get your arms in the proper position under the bar).

Do it regularly and you’ll notice an improvement in your posture and performance in no time.