If you play and throwing sports or lift weights overhead shoulder mobility is extremely important. Check out this post on some tips for how to improve overhead shoulder mobility and why it is important.
Your ankle is a complex joint between your leg and foot made of multiple ligaments. These, like all ligaments in the human body, provide stability, send information to your brain, and direct how your joint moves. An injury in 1 or more of these ankle joint ligaments is exactly what an ankle sprain is.