Experience From - Bryan Beel , Sean Greenhill , Will Brown, Robert Thomas, Janet Whitesell, Rich Schick,
I saw a product at the local outdoor store that is a neck wrap for hot weather. It looks completely flat (or, at most, 1/4 inch thick) but the directions say that soaking it activates a gel on the inside that will keep you cool for 24-36 hours (!). It was only about 6 bucks (US dinero) and I "almost" bought one to see how it worked. But it's not hot here, yet.
Has anyone seen anything like this, and what are your impressions? Name is something like "Hunter's and Fisherman's Wrap," it's light brown, about 24 inches long and fairly thin.
I bought a few of these last July when I was in Queensland for the GC Marathon, for about A$6. They're full of a gel which absorbs water (you soak it for a few hours) and then place them in the freezer. The gel doesn't go snap solid, just provides a very cold presence for a couple of hours in the heat (not 24- 36 hours). They easily recharge with another quick soak in cold water.
The problem I found with them was that over a period of a few months this summer the gel slowly leached out of them and they became useless. I certainly could have used them the weekend before last at the Six Foot Track Run (which was very hot) but I'd already thrown them out.
They did work well for a few months though. Whether this is a different, longer lasting brand is another question.
I picked up a thing called a Kool Tie while I was there. It's essentially a bandana that has been sewn together into a tube with some kind of crystals inside. I didn't have time to read all the literature, but you soak this thing in water for a while before you wear it, and there's supposedly a big cooling effect on your carotid arteries. Anyone try one of these?
Yes any of the cold collars will work to help you feel better in hot weather. These cold collars generally use some kind of gel that you freeze, then take out of the freezer then use.
I personally use an ice collar that I make myself. The collar I made is from a long sleeve tee shirt sleeve. I cut off the sleeves, sew them in half length wise, then cut it to fit around the neck. I make two separate pockets, a left side and a right side. This helps to keep the ice from shifting around to one point. I make a separate Velcro closure for each pocket and a separate piece of Velcro to attach the collar around the neck. You can adjust the size of the collar to meet your own cooling needs and comfort. It's easy to make and works very well.
The advantage of an ice collar over a gel or other type of cooling collar is that the gel collars or other materials that you cool will warm up with use. The ice in the ice collar will melt ice cold water onto your neck and running shirt. This has a powerful additional cooling effect beyond just having something cool near your neck. You can refill the ice collar at aid stations, so you can keep the collar working at its best. Even running in over hundred degree temperatures can seem nearly cold while using an ice collar.
"I always thought the purpose was to cool off the hypothalamus, which is the body's thermostat"Now this makes no sense to me. If you cool off the thermostat, you fool it into thinking everything is "cool", and it instructs the body not to bother dumping any more heat. Sounds like a very dangerous situation to me. If you have an air conditioned house and you put an icebag on the thermostat, that air conditioner is never going to come on, and the house can get beastly hot.
On the other hand cooling down the carotid arteries makes a lot of sense. You do want to cool down the blood that is going to the brain. Most all your organs can stand hotter temperatures than what the brain can stand. And since the blood circulates throughoutthe body, cooling the blood at any point is bound to help overall.
All these products work by cooling blood in the capillaries - the little tiny vessels in the skin at the surface. If one were successful at cooling the hypothalamus, they would chill out. The brain would be too cold to function and at best they would be rendered unconscious at worst dead. The same would be true of anything that effectively cooled the carotid blood flow. These claims are nothing more than marketing claims of the either unethical or uninformed.
I would be a little leery of anything that pressed on the carotid area too much for a couple reasons. Chronic irritation over the carotids can stimulate cholesterol plaque formation which over time can lead to strokes. A study some years ago showed an increase rate of strokes among health care workers with a habit of hanging their stethoscope from their neck. (I carry mine in my labcoat pocket.) The other problem is stimulation of the carotid sinus. This is a receptor in the area which when massaged tries to get the heart to slow down. Won't effect most people when exercising though I have to wonder about it when folks are fatigued, dehydrated and calorically depleted.
I tend to favor systems that put the coolant up on the scalp. Other than triggering an occasional headache I can't think of any potential problems. There are plenty of capillaries in the area, and systems that have melted runoff will still pass over the neck.