Getting Used to Heat and Getting Used to Cold Are One Job

Getting Used to Heat and Getting Used to Cold Are One Job

The first days of summer are the hardest. Then, at some point, the same heat becomes bearable. Winter is the same: the first cold bites unusually, and a month later the same temperature is less fierce.

We call this "getting used to it." But the body does not keep a summer apparatus and a winter apparatus separately. It shifts the setting of the same one.

The Body Moves a Setting

Several things actually happen while the body grows used to heat.

Sweating begins earlier. Sweat that once required the body to grow hotter now comes with a smaller rise. Vessels near the skin open earlier too. And the water share of the blood increases, giving the circulation more margin. Endure it for ten days or so and these changes settle in, with the heart rate falling as well.

Growing used to cold has the same structure with the direction reversed: the threshold for releasing heat moves back, the share sent to hands and feet is adjusted, and heat production grows somewhat busier.

Different apparatus is not called up for the two seasons. Only which way the same regulator is set differs.

Which Is Why a Changing Season Is "Mid-Shift"

Seen this way, why the change of seasons is so trying reads differently.

The body in a changing season is not broken; it is mid-shift. Shifting takes time. When cold air arrives suddenly on a body still set for summer, autumn has to be got through on a summer setting. Those few days or weeks are uncomfortable.

And the wider the shift, and the less time to make it, the harder it is. Days when the temperature swings more than ten degrees are especially so: no sooner has the body set one way than it is asked for the other.

Tests Do Not Catch the Shifting

Here the story meets what this part is about.

Tests are generally taken indoors, in comfort, once, at rest. Under those conditions the body has already settled to the temperature of that room. So the state of working hard at a shift does not leave much trace on the report.

That is how "every change of season is like this, and the tests are always normal" arises. The test did not miss it; the conditions of testing had already excluded it.

I Look at Narrowing the Shift

In the consulting room I do not simply call this "being sensitive to seasons." I look at how abruptly the shift is being made.

The shifting itself is the body's work. Its width and speed, though, can be worked with a little: narrowing the gap between indoors and outside, avoiding the coldest or hottest part of the day, layering clothing rather than changing it all at once. It also means someone who struggled last time can prepare before the next change arrives.

That said, if breathlessness, chest tightness, or fever with weight loss come regardless of season — that is not a story about seasons. Tests to find the cause come first.

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The body does not learn something new each season. It moves the one thing it has toward summer, or toward winter.

If a change of season is especially hard on you, it is not weakness. It may be that the body is mid-shift. Once it has moved, the same weather becomes bearable.

Related Reading

• Tests Look at the Body of That Moment — matched conditions and the body in daily life
• The Same Place Gives Way at Every Change of Season — where it shows first during the shift

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Sources

• About ten days of heat acclimation raised resting plasma volume by roughly 6.5% and lowered heart rate, with sweating beginning earlier — Heat acclimation improves exercise performance, 2010
• During heat acclimatisation the thresholds for cutaneous vasodilation and for the onset of sweating are both lowered — Heat acclimation improves cutaneous vascular function and sweating, 2010

Written by Dr. Heo Ji-young (PhD in Korean Medicine Pathology, Kyung Hee University · former Research Professor of Herbology, Kyung Hee University)