Sprained and swollen ankle:
1. Strap it up. Soak bandages in cold water, wrap ankle tightly. Do this for several days. 2. Keep OFF the ankle for several days.
3. When you can walk on it again, gradually increase pressure you put on the ankle until you are walking normally again. Until you can resume normal walking gait without favouring the other side, you have no business working out at all!
4. Then, what I have used and which helps a lot is swimming. Somehow the foot motions and kicks help me resume full range of motion and gain strength back in the injured ankle. Couple of weeks swimming and I'm back to powerwalking and light running. But you have to build back up SLOWLY! I'm not a fan of swimming either. But it works. It's short term and will get you back to running.
If you are having discomfort after this, you should not be running. No treadmill. No barbells! If you are beyond the swelling and bruising stage and discomfort/pain/inability to put weight on the foot/walk normally persist, then you should get an x-ray. A very bad sprain will not heal without a fixed kind of bandaging around the ankle, lower leg. I know, because I have been through this.
After plaster/stiff bandage comes off, resume re-hab from #3 onwards.
Clare