Feeds

Why do some people feel the cold more than others?

Some like it hot

Intelligent flash storage arrays

Also in this week's column:

Why do some people feel the cold more than others?

Asked by Mick Higgins of Toronto, Canada

Human body temperature is a measure of the body's ability to keep, generate, or get rid of heat as the need arises. The body is very adept at maintaining temperature within a narrow and safe range, despite occasional huge variations in the room temperature.

But some bodies are more efficient than others. Even bodies of the same height and weight may differ dramatically in the ability to maintain body temperature.

Humans also differ in their preferred room temperature. Some like it warmer, some cooler. This is called thermal comfort. Thermal comfort is not merely physical, but psychological too. In one's choice of preferred temperature, besides psychology, other personal factors come into the equation. Two of these are clothing levels (their insulation value) and activity level (their effect on body metabolism).

Stephen Turner, an engineer with the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) in Atlanta, said: "Activity level is a key factor, as illustrated by the story of an adult skiing down a mountain with a child bundled in warm clothes on their back. At the bottom of the hill, the adult is sweating, but the child is bitterly cold. Difference in metabolic rate is the cause."

ASHRAE maintains and periodically revises international thermal comfort standards. But this is not the end of the story.

According to Paul Spry, a consultant engineer in Canberra, Australia, there is also evidence that a person's thermal comfort perceptions are influenced by external factors such as recent weather.

He adds: "Another consideration is the difference between sensory and psychological reactions. A particular person may say it is cold or cool, but if you accept this as the final judgment (as a desire for a higher temperature) you are at risk. Further questioning may reveal that though the person is 'cold' or 'cool' they may be optimally comfortable (desire no change for thermal comfort reasons)."

Interesting facts

  • When you are hot, the blood vessels in your skin expand (dilate) to carry the excess heat to your skin's surface where it is released. You sweat and as the sweat evaporates, it cools the body.
  • When you are cold, your blood vessels in your skin narrow (contract) so that blood flow to your skin is reduced to conserve body heat. You may start shivering, which is involuntary, experience rapid contraction of the muscles. This extra muscle activity helps generate more heat. Both processes help keep your body temperature with the required narrow and safe range.

Stephen Juan, Ph.D. is an anthropologist at the University of Sydney. Email your Odd Body questions to s.juan@edfac.usyd.edu.au

Providing a secure and efficient Helpdesk

More from The Register

next story
GRAV WAVE DRAMA: 'Big Bang echo' may have been grit on the scanner – boffins
Exit Planet Dust on faster-than-light expansion of universe
SpaceX Dragon cargo truck flies 3D printer to ISS: Clawdown in 3, 2...
Craft berths at space station with supplies, experiments, toys
That glass of water you just drank? It was OLDER than the SUN
One MEELLION years older. Some of it anyway
NASA rover Curiosity drills HOLE in MARS 'GOLF COURSE'
Joins 'traffic light' and perfect stony sphere on the Red Planet
Mine Bitcoins with PENCIL and PAPER
Forget Sudoku, crunch SHA-256 algos
'This BITE MARK is a SMOKING GUN': Boffins probe ancient assault
Tooth embedded in thigh bone may tell who pulled the trigger
Big dinosaur wowed females with its ENORMOUS HOOTER
That's right, Doris, I've got biggest snout in the prehistoric world
Japanese volcano eruption reportedly leaves 31 people presumed dead
Hopes fade of finding survivors on Mount Ontake
Canberra drone team dances a samba in Outback Challenge
CSIRO's 'missing bushwalker' found and watered
prev story

Whitepapers

A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Beginner's guide to SSL certificates
De-mystify the technology involved and give you the information you need to make the best decision when considering your online security options.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.