Brief Answer:
Ankle care information:

Detailed Answer:
Hello and welcome,

Depending on the severity of the sprain, you will need to wear an ankle support/brace from between 10 days to 6 weeks. Without the advantage of examining your ankle, it is hard to know exactly how long, but usually 6 weeks is more for a 3 rd degree sprain, and I am guessing from your description of the ankle having been swollen (therefore more than 1st degree) and having had pain (likely less than 3rd degree) that you may have a 2nd degree sprain. But I can't be absolutely sure.

With any significant ankle sprain, and especially since you mentioned it is a weak ankle, rehab exercises are imperative. After your ankle has healed exercises can be started. Proprioception, or position sense, can be lost in an injured ankle, leading to more sprains. If you are able to self refer to physical therapy, that might be the easiest way, because they have balance boards and other equipment for retraining your ankle's position sense.

Here are some general exercises to make the ankle muscles strong again:

Ankle Circles
Sit on the floor with your legs stretched out in front of you. Move your ankle from side to side, up and down and around in circles. Do 5 to 10 circles in each direction at least 3 times per day.

Alphabet Letters
Using your big toe as a "pencil," try to write the letters of the alphabet in the air. Do the entire alphabet 2 or 3 times.

Toe Raises
Pull your toes back toward you while keeping your knee as straight as you can. Hold for 15 seconds. Do this 10 times.

Heel Raises
Point your toes away from you while keeping your knee as straight as you can. Hold for 15 seconds. Do this 10 times.

In and Out
Turn your foot inward until you can't turn it anymore and hold for 15 seconds. Straighten your leg again. Turn it outward until you can't turn it anymore and hold for 15 seconds. Do this 10 times in both directions.

Resisted In and Out
Sit on a chair with your leg straight in front of you. Tie a large elastic exercise band together at one end to make a knot. Wrap the end of the band around the chair leg and the other end around the bottom of your injured foot. Keep your heel on the ground and slide your foot outward and hold for 10 seconds. Put your foot in front of you again. Slide your foot inward and hold for 10 seconds. Repeat at least 10 times each direction 2 or 3 times per day.

Step Up
Put your injured ankle's foot on the first step of a staircase and your uninjured foot on the ground. Slowly straighten the knee of you injured leg while lifting your uninjured foot off the ground. Slowly put your uninjured foot back on the ground. Do this 3 to 5 times at least 3 times per day.

Sitting and Standing Heel Raises
Sit in a chair with your injured foot on the ground. Slowly raise the heel of you injured foot while keeping your toes on the ground. Return the heel to the floor. Repeat 10 times at least 2 or 3 times per day. As you get stronger, you can stand on your injured foot instead of sitting in a chair and raise the heel. Your injured foot should always stay on the ground.

Balance Exercises
Stand and place a chair next to your uninjured leg to balance you. At first, stand on the injured foot for 30 seconds. You can slowly increase this to up to 3 minutes at a time. Repeat at least 3 time a day. To increase the difficulty, repeat with your eyes closed.

I'm sorry I can't tell you exactly how long to use the brace, but I hope this information helps.

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