Many of these are yoga positions. Work to achieve them slowly. ~ Muscle assisted shoulder stretches: tricep stretch, one arm over the head, both arms over the head, cow face yoga position, grab an elbow be.
These were really useful to me over summer where i had no access to a gym, thought i'd share, hope you guys find them helpful :) - Tap the pin if you love super heroes too! you will LOVE these super hero fitness shirts!