I have always been concerned that people generally underappreciate how severe an ankle sprain is. Perhaps this is due to twisting your ankle as a child and being told to "walk it off" by your school gym coach. Even so, every time you sprain your ankle, it causes damage to the ligaments that support the ankle joint and weakens it. A twisted ankle can even cause a severe fracture in your foot that can require surgery to repair.
Studies have shown that more aggressive treatment of a sprained ankle resulted in a much more complete recovery. This can include immobilization in a fracture walker boot and the use of crutches. After approximately two weeks, more weight can be placed on the foot and ankle and soonafter, you will be ble to shift from the boot to an ankle brace. You ultimately can expect to return to full activity 6-8 weeks after the injury.
I recently came across a great, short article in the Patriot Ledger by Dr. Benjamin Thompson, a sports medicine orthopedist in Massachusetts, who also feels that sprained ankle are largely undertreated and ignored.