Benefits on running completely soaked?

Question

Are there any benefits on running soaked in water?

I've been to a half-marathon length race recently. Temperature was high, above 25 ºC. There were runners who, in the provisioning sites (I'm not sure about the correct word, sorry, I mean the intermediate points where the organization offers you liquid or solid refreshments), took several bottles of water, emptying the first ones on themselves and drinking from the last one, looking like they just fell in the pool.

I was wondering if doing that provides a real benefit (like improved refrigeration, less sweating and minor loss of hydration).

I'm more likely to think it is abusive and can lead to running out of water for the other racers, but I'm interested in the physiologic and performance parts rather than in the ethics.

Probable benefits are the cooling "sensation" and some extra help with thermoregulation. But, does it provide a lasting thermoregulation or is it counterproductive soon? I'm thinking of water nebulization in fire fighting, which is more effective than drenching for dropping the room temperature.

After the discussion and rethinking what words to use in searches I've found some contradictory related information:

• Dehydration prevention tips: Change into dry clothing as soon as you can if your clothes get soaked with sweat.
• Dehydration and Heat Injury: Clothing that is dry slows down evaporation of sweat, but once wet, cooling continues. Thus, changing into dry clothes during transitions is not a good idea.

Answer 1

Cooling of the body largely happens via evaporation of water, whether it's the water in your sweat or an external source. There's an additional cooling that happens when doused with water in that some of the heat is likely to be transferred to the water, which then drips away. On the other hand, you're increasing the amount of weight you're carrying, particularly if you've got absorbent clothing on, and you're increasing the risk of chafing from the wet clothes.

On a side note, and partially addressing your edit to include commentary of where you start getting negative effects, sweating works via evaporation. Contrary to the belief of many, being soaked in sweat is not a good thing, because it means that your body can't keep up with the cooling. Ideally, the sweat is evaporating as fast as it comes off of your skin, so you wind up with a faint sheen at worst. Wearing clothing complicates the process because the cloth can trap the moisture and, when you have enough water in the clothing, it acts as insulation, trapping heat in the water on the inner layers. Your body will react to this perceived extra heat by sweating more. If your clothes are already saturated, the water will just drip away, providing some small benefit, but preventing the natural cooling through evaporation. In colder weather, as per your second link, it will also mean loss of proper thermoregulation, and thus an increase of risk of hypothermia, because your body will stop sweating, but the cooling process will continue to occur as water is evaporated off of the surface.

Ultimately, soaking yourself in water when clothed is a bad idea. Soaking yourself in water where you don't have clothes (c.f. topless runners) might have some minor benefit, but will largely be wasted water. If you're training to run completely soaked (say, someone training for a Tough Mudder-type event, or a soldier training for operations in bad weather), then you get the minor effect of learning to live with the side effects, but that's like discussing the benefits of running with bruised feet.

As a postscript, there's a voice in the back of my head saying that pouring water over yourself might also mess with protective oil in your skin, increasing the risk of sunburn and chapping in much the same way that swimming or licking your lips can increase the risk. I don't think that would apply here, since it's a relatively small amount of water that's going down the surface (versus prolonged immersion as in swimming or the pressure of licking one's lips), but it's something to consider.

Answer 2

Agreed with Sean on weight increase due to the water and possible chaffing.There is a good reason why our bodies sweat. Its a cooling mechanism. You should be more worried about keeping your self hydrated rather than drenching yourself in water.

An arbitrary example;

• Imagine a water-cooling system for a high performance computer that is number crunching complex computations. You need to cool down the hot water generated by the components of the computer. This is done by slowly pushing the water through a radiators fins with the assistance of fans (if necessary) and then pumping back cool water to cool the components again.
• The same goes for your body. Your body will pump hot blood to the external veins (radiators fins) under your skin, thus allowing you to sweat and wind (fans) will remove heat off your skin allowing the blood in the veins to cool down. After this has been done,cooler blood is then transferred to areas where cooling is required.

Putting water on yourself externally will only give temporary results.

Some advice I think you already know, but I am stating some points for the other members interested in this board;

1. Keep yourself hydrated with water. Sugar sports drinks are good for instant energy like 100m 200m, 400m dashes, once your blood sugar levels drop after the instant rise, you will feel tired and sluggish. For a marathon runner, I believe that hydration with only water is essential before(the day before), during and after the race.
2. Focus on your breathing technique, an efficient marathon runner who has the right breathing technique can have a better chance at winning a race. You will also be able to control your heart rate better thus less chances of you dehydrating

All the best with your races.

Answer 3

If I'm running in a hot race then I'll dump a glass of water over the back of my head (targetting the area just where my neck meets my head).

Why? I want to reduce the risk of heat stroke and other heat related problems. If that area of the brain gets too hot then I have a very serious problem. More than that, I find that sense of relief it brings to be very useful. It helps me convince my body that things are under control and it should just keep on going a bit longer.

I wouldn't do it for a half-marathon - why waste the time when you're only out for two hours?