I just got back from a bad sprain... Riding a bike is what the doctor told me to do... It was important to just go easy and not push it. Several of my friends (who have had a broken/sprained ankle)have cut their recovery times in half by riding a little. I like the idea of cold and heat too... I have used that several times for injuries.
I have been told that I could start climbing as soon has I could hop or stand on the hurt ankle/foot. I was skeptical because I still had quite a limp. I did and it felt great... it made my foot feel even better. It stretched out the muscles and really improved the range of movement. CAUTION should be taken because if you start too soon and/or fall on an injury it can really complicate things.