Horizontal adduction and internal rotation of the humerus are two primary functions of the pectoralis major muscle. To stretch this muscle, you would perform 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 your thighs against the bar, you help deload and stabilize the body, allowing you to relax further and heighten the stretch. The bar also lets you pivot from the hips, promoting more external rotation around the shoulder. It might not look like much, but try it — 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 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.