(Image credit: Shutterstock) When I go to a yoga class (which is roughly four times a week), I always show up 10 minutes early so that I can have a quick stretch on my mat. The first stretch I turn to every single time to open my upper body is my take on a restorative pose called supported fish, but I like to add a little extra for my shoulders and lats. I have very tight chest and shoulder muscles, alongside a past rotator cuff injury and some work-related hunching over the years, which have all played a role in creating lots of upper-body tension. How do you do it? Aim to hold the stretch for at least 30 to 60 seconds, if not longer. As you hold the stretch, allow gravity to relax your shoulders and elbows and try to breathe in and out deeply. Don't force anything, but do gently draw your elbows down toward the mat. Don't force anything, but do gently draw your elbows down.…