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By Samantha Kramer, AccuWeather.com Staff Writer

July 15, 2012; 7:47 AM

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Getting used to the heat outdoors allows us to sweat more, which helps our bodies cool down faster. (Photo courtesy of Photos.com)

When temperatures reach unbearable levels, we get by with a little help from our metabolism.

When intense heat blasts our bodies with temperatures we're not used to, spending all day in the air conditioning may seem like an obvious way to cool down.

But Dr. G. Edgar Folk, a physiology professor in the University of Iowa Carver College of Medicine, said it prohibits the body from adjusting to the heat.

According to Folk's research, a healthy body can adjust to an extreme climate in two weeks by becoming "outdoor acclimatized."

Studies show that going outside and getting used to the heat can promote physiological changes to lower heat strain, the National Collaborating Centre for Environmental Health reported.

By going out in the heat, the body's salt concentration of sweat progressively decreases, while the volume of sweat increases. Blood vessels dilate, which brings heat from the core body areas to the surface so it can be dissipated and our bodies can cool down more quickly.

This explains why there is a larger amount of heat-related deaths in early summer months - people don't have the chance to adjust. But by August and September, we have already become physiologically acclimatized to extreme heat, according to the NCCEH.

The same concept applies to cold weather. Athletes and hikers will often train for weeks in the cold to acclimate their bodies to the different conditions.

Acclimatization isn't just short-term. It also explains the difference in body structure and chemical make-up of people around the world, said John Blangero, a Department of Genetics scientist at Texas Biomedical Research Institute.

The June and July heat waves that scorched the Northeast to unusually high temperatures may have some wondering how people living in southern tropical climates could ever put up with such temperatures on a regular basis.

Blangero said acclimatization also plays a role in genetic environmental adjustment.

"Temperature is an important environmental force," Blangero said. "There's lots of different human physiological stems that will play a role in your response to heat."

It explains why populations in Africa are better equipped to deal with the heat because of their skin color and body form, he said.

Long, slender bodies tolerate heat better because a greater surface area exposes more skin to perspire. More body fat means less skin surface in relation to that person's weight, which is why the Inuit peoples in Arctic regions tend to have thicker bodies to adjust to the cold.

But, as Blangero points out, at some point on the thermometer, everyone will succumb to the heat.

"The ability to maintain water reserves, the ability to keep electrolyte balance... it differs from person to person. Except at some point, heat stress will ultimately affect everybody," he said.