Why are we trembling from cold?
Shivering – protective reaction of the body to reduce body temperature. She, by the way, is peculiar to all warm-blood, not only a person.
The fact is that the temperature range in which biochemical reactions can flow, providing our livelihood, rather narrow. At elevated body temperature, proteins lose its catalytic activity, that is, they cease to accelerate chemical reactions occurring in the body. At low temperatures slowing biochemical reactions and the lower the temperature, the more likely that they stop altogether. In this case, the person will die.
Shiver – the most effective way to "warm up" the body. Skeletal muscles of any warm-blood, reducing, produces a certain work, resulting in heat. Shiver makes it possible to correlate the cost of energy and the resulting heat. With other types of skeletal muscles, such as run, this balance is shifted towards the energy spent. That is why the freezing dogs do not run in circles to warm up, but roll up with eating and tremble – so they minimize heat and energy losses.
With sudden cooling, heat leaves from the body surface to the environment. Until a certain moment, this situation is not considered by the body as a critical. But if the heat loss continues, the first of the protective mechanisms turns on: the subcutaneous capillary network is dramatically narrows, reducing the subcutaneous blood flow. The body is trying to preserve heat for vital organs – internal, sacrificing less important – surface. We feel cold. If the heat loss at this stage does not stop, the body temperature decreases. Usually a person begins to tremble when its body temperature drops to about 35 ° C. But it happens that the tremor occurs and at a lower temperature.
In any case, to hinder it, it is necessary to limit the heat loss of the body – for example, warm.