First, I recommend that we all take a first aid course so that we can learn how to properly take care of an injury when we first get hurt. Drawing from my American Red Cross experience, check out the following information:
For a twisted ankle, which is by far the most common injury when exercising, wait to remove your shoe until you get home. The shoe helps to support the injured area.
Follow the R.I.C.E. method to treat almost any kind of injury:
Rest- Allow the area to rest for at least a few hours
Ice- Put ice on the area, even if you don't see any swelling
Compression- Light compression can help to alleviate swelling
Elevation- Elevate the area to reduce blood flow
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The R.I.C.E. method works for pulled muscles as well. You might want to try alternating heat and cold if it helps with the pain and swelling.
Give yourself a good two days of rest for the area. After that, you can try a light workout on the area, but if you have any pain at all, you need to give yourself more time to heal.
Don't ever workout on an area that's injured- you can further injure the area, and it will just take even more time to get back to your regular level of exercise!
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