On the advice of a good friend I am posting a proper way to cool down during a race without adversely affecting your outcome. See nothing upsets a race faster than discomfort, either from the weather or self induced (like blisters or chaffing, but thats for another day). I am going to address how to keep your head cool and your feet dry.
For your feet. First things first, you need to use a pair of worn in shoes and proper socks for a race. Its a myth that running shoes need to be 'broken in' nowadays but it does take few miles done over a couple of short runs to 'mold' the insert and footbox to your foot. This limits blistering and goes back to a smart training concept, "never introduce something to a race that you haven't tried at least three times in training". For socks, never cotton. My recommendation is to move away from thick cushioning socks and into Dri Fit, or my favorite DeFeet socks. If your apprehensive of changing to a thinner sock because you feel your feet need additonal cushioning than you either need to change shoes or upgrade insoles to something like Sorbathane, which is my favorite. A high performance sock will move liquid from your skin to outside of the sock, which will prevent blistering. Also the thinner performance sock will be made of a slicker material that will prevent hot spots. (Sidenote: before anyone thought about using polyester or nylon in a running sock we would wear Leggs knee high or ankle high pantyhose under cotton socks so that we wouldn't get hot spots or blisters).
As for the water, always over the back, never over the front or right over your head. It will run down your leg and into your shoes. Never lean over to just hit the back of head and let it run off the front. You may think the 'over the sink' style will work but if your deep into a race your body has compensated to a certain momentum equilibrum and when you lean over you could suffer a major shift of blood flow and pass flat out, (but at least its in a water station and lots of people are there to help you wake up).
The best way to cool off is to take off your hat and soak your hat, shake it out and put it back on. If your lucky enough to get ice, put just a few cubes in your hat. If your in a real hurry, take a drink then splash the small amount left in the cup over the back of your head and back so that most of it stays high and minimizes running down your legs.
Never, never run through a water sprayer. Sometimes at a water point, or a station set up by a fire department or just a kind neighbor living on the course, they will shoot a stream or spray of water over the runners to cool them off. Avoid at all costs as it will soak your shoes and you get the inevitable skin rubbing and blisters. Its better to have hot feet then blistered feet.
Now if its raining and depending on the distance, carry a back up set of socks pinned in a bag under your shirt or tucked into a pocket or utility belt. Its worth the hassle of carrying them and protecting your feet than not. Its a cost to benefit analysis. (Sidenote: If its a long race and in inclimate weather I will wear a water/utility belt. Especially if its cold, I will put in it some lip balm, a small chemical hot pack (in hot or humid marathons I might carry a small chemical ice bag) and just a few other things.)
