Cooling off effectively
The new device designed by scientists removes excess heat from the body much more effectively than traditional methods.
OVERHEATING IS a serious concern when exercising in hot environments, wearing insulating clothing, or during high intensity activity. The age-old method of cooling oneself is to stand before fan or sprinkle cold water on the face or some such tactic. While such solutions often provide temporary relief and make one `feel' cool, they are generally ineffective in removing heat from inside the body.
This is because these treatments are applied to the skin's surface and they have difficulty penetrating the body's insulating layers of tissue.
Such superficial treatments can even have a deleterious effect in that the cold temperatures of these remedies can result in a vasoconstriction of the peripheral blood vessels and actually cause a reverse of the desired effect by shutting down the natural heat dissipation mechanisms.
Elevated core body temperature is a problem for many, including athletes, industrial workers, miners, fire fighters and soldiers. As the temperature of the body's core organs (heart, lungs, liver, kidneys, and brain) rise, fatigue sets in and strength, endurance and cognitive functions deteriorate rapidly.
Two scientists from Stanford University, Dr. Dennis Grahn and Dr. Craig Heller of the Department of Biological Sciences, have, after a decade of research, come up with a novel and very effective way of quickly removing excess heat from the interior of the body and providing real relief to the affected person. Called Rapid Thermal Exchange (RTX), this technique was originally developed on the principles of mammalian thermoregulation. All mammals have `radiators' — specific regions of body surface designed for dissipating excess heat from the body core to the environment.
A dog's tongue, or an elephant's ears are examples. Blood is preferentially pumped to these surfaces when metabolism increases as it does during exercise. In humans, some of these radiator surfaces are found in the palms of the hands and soles of the feet. Heat is dissipated in these skin regions through specialised blood vessels called arteriovenous anastomoses (AVAs).
Using a specially developed machine, the Stanford University scientists found that as much heat could be extracted from the palm of one hand as across the entire body during maximal sweating.
Unofficially known as the Glove, this shoebox-size appliance houses a steel plate maintained at a low temperature by a hose connected to a cooling unit. A second tube removes water heated by the warm blood, while a third tube produces a slight vacuum.
The person who requires cooling puts his hand through a cuff that seals at the wrist and places his palm on the plate. The vacuum is maintained to increase circulation in the hand, and the plate cools the blood.
The person feels refreshed and his muscles experience an immediate boost of energy. In a small pilot study, Grahn and Heller had subjects pedal to exhaustion in a `hot' room wearing two sets of long underwear, plastic rainsuits and hooded sweatshirts. After the subjects' temperatures rose to an average of 102 degrees, they stuck one hand in RTX machine. Their body temperatures dropped to normal range within 15 minutes. When the subjects cooled on their own in the same conditions, core temperatures remained elevated for 30 minutes.
It has tremendous implications for enhancing strength and endurance training. It helps keep core body temperature within normal range for optimal muscular performance.
If you stay cool, less blood is shunted to the skin for heat dissipation, making more blood available to service working muscles with delivery of oxygen and nutrients, and removal of metabolic by-products.
Use of the technology reduces the rate of core temperature rise during exercise and increases the rate of core temperature decline following exercise resulting in increased speed, strength and endurance and reduced risk of heat and dehydration related injuries (e.g., cramping). Although use of RTX technology is now focussed on sportspersons, others who work in the heat such as fire fighters and miners could also benefit.
Those suffering from chronic diseases that are exacerbated by heat, such as multiple sclerosis, could also make use of the cooling technology. Heart attack and stroke sufferers could be cooled to reduce tissue damage. By reversing the process, cancer patients could be warmed to enhance the effects of chemotherapy. To spread the commercial availability of RTX technology, the two inventors founded AVAcore Technologies (www.avacore.com), in 2000.
N.N.Sachitanand
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