If you dump in the middle of a churning river, the first thing to remember is to hang on to your paddle, says veteran river kayaker Arlene Burns. It extends your reach by five feet [1.5 meters], making it that much easier for someone to haul you back into the raft—always the preferred option.

But if there's no one nearby to help, Burns advocates "the Mark Spitz school of self-rescue: Swim like hell. I know, everyone says to lie on your back with your feet up, so you can flex your knees and bounce off rocks. But I say, be flexible."

Sometimes, when you're above a rapid, a few vigorous strokes can help you avoid a nasty hole or massive rock downriver. (Assume the traditional defensive posture before you enter the white water, though.) If you're below a rapid, swim for shore—the next big one may be just around the corner.