When
something is considered to be “hot” or “cold” what is it that really determines
the reality of that feeling? Is it the temperature of the two objects? Is it
the difference in that temperature? Or is it just the rate of the transfer of
heat between the two objects? When determining what you like in a sleep system
in relation to these ideas can be very important to your comfort while you
sleep.
What are
heat, specific heat, and heat transfer and how does it affect you?
Heat is the
kinetic energy of an object measured in joules, or the vibration energy of the
molecules. Specific heat is the amount of energy that has to be put into an
object in order to raise the object one degree centigrade, specific heat can
also be visualized as the ability of a substance to resist heat change. Heat
transfer is the major thing that a sleeper should look at when trying out a
bed. Heat transfer is based on the contact that you and your bed share as well
as the temperature difference; it is an exchange of vibrations. The more in contact
you are, the more heat transfer that will occur between you and your mattress,
so when you sleep on a body conforming mattress you are allowing for a higher
rate of heat exchange between you and your bed. Substances with a high specific
heat and density, for example the gel based memory foams in the I-series by
Serta, will take longer for your body heat to warm up so when you climb into
bed they will have an initially cooler feel for a longer period of time.
When you
look for the extended feeling of “coolness” there are many different factors.
The most important one is the fact that you are giving off a fair amount of
your heat and it is not retained in the covers with you. The air feels cool all
the time right? This is because for every molecule you warm up it leaves your
vicinity to be replaced by another one that is cooler. Modern beds are working
of this concept of moving and dissipating heat like the new mattress lineups
like the Tempur-Breeze series from Tempur-Pedic. The Tempur- Breeze is using technology to allow
for better air flow and heat transfer using thick celled foam walls to allow
for more movement of heat and a more breathable model that channels the heat
out through the air passageways.
Other
things to consider when sleeping that a spring mattress, though it may seem to
make you sleep cooler isn’t always the best option to consider. Blood flow is
important when you sleep because it keeps you from tossing and turning in your
bed and keeps you rested and healthy, but when there is more blood flow your
body will sleep hotter. Blood is one of the major contributors that transfers
and transports heat through the body. Spring mattresses can restrict blood flow
by increasing pressure in the wrong areas of the body whereas memory foam is
pressure sensitive and distributes and evens out the pressure on the body. When
considering your mattress take into account the time you will spend beyond the
time in the store and make a careful and thought out decision, for many hours
will be spent on a mattress.
