Standing Reach and Lean Lat Stretch
This is much simpler than the other side stretch, but it’s also less effective. As a result, it works best for people who have tight lats or have not done much stretching in the past. It is great for providing initial increases in flexibility until your body is ready for more intense side stretches.
To perform the stretch, stand in a comfortable and stable position. Then raise one arm straight up and reach as high as you can above your head. Sometimes just doing this will cause a stretch in the muscles down the side of the arm that is raised.
To increase the stretch, lean/bend away from the side you are stretching. If you want to stretch your right side, start by reaching overhead with your right hand and then lean with your body to the left, while continuing to reach with your arm/hand.