Wrong. They ice the horse's leg after hard rides in order to lower the horse's body temperature, prevent swelling, and promote healing. Nice try though.
What? They 'ice' them?
First you said they hose them down!
Have you ever noticed that horse trainers hose down their horse's legs with cold water after a hard run or race? Why do you think they are doing it?
You and the OP both have SERIOUS problems with water and understanding the terms used to describe how it can be used in conjunction with recovery.