We have sold and experimented them for a while and in this article, we will explain to you how does thermal clothing work and how you should choose the right ones for you.
One of the most basic techniques in the field of backpacking and hiking is the method of dressing in layers.
This method requires us, hikers, to wear several layers of clothing, and in this way allow us to be ready for any weather encountered during the trip.
The first layer, which is worn in the layers of clothing, is the thermal clothing (BASE LAYER).
Thermal clothing is the first and most basic layer, which comes into direct contact with our bodies, hence the great importance of this item. In fact, thermal clothing will almost always remain on our bodies, even when it is in warmer weather that will allow us to lower the rest of the layers.
In order to understand how to choose thermal clothing, one must first understand the mechanisms used by our bodies to regulate body temperature, and how does thermal clothing work and helps with it.
How does thermal clothing work
In order to understand that, first, we have to understand our body’s physiology
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Physiology of the human body
One of the basic and known facts is that the warmth of our bodies should be kept around 37 degrees Celsius.
This temperature of 37 degrees Celsius is called the core temperature.
If the body temperature rises or falls from this temperature, we will begin to experience signs that will eventually lead to (in extreme cases) a loss of consciousness.
Our body’s way of maintaining the warmth of the core is divided into two: a cooling mechanism and a heating mechanism.
As we exercise, the warmth of our bodies begins to rise.
As a result, the sweating system increases its activity.
This system, which is in operation throughout the day and in any weather, increases the rate of sweat, sometimes up to two liters of water per hour.
The sweat (like water) has a very high heat absorption capacity. In fact, evaporation of a liter of sweat will absorb about 600 calories from the body and lead to a cooling of the body. On the other hand, the sweating mechanism has several problems:
- Excessive sweating – in some cases our bodies produce so much sweat that it is not able to evaporate it. Excessive sweating in a hot environment can cause skin sores and mainly physical and psychological discomfort. In a cold environment, hyperhidrosis can also be dangerous and cause the body to cool down and even drop to the core temperature and in extreme cases to hypothermia.
- Fatigue – The process of cooling and sweat production requires a lot of energy from the body. This energy investment eventually leads to fatigue of the body, preventing us from continuing our journey.
During the thousands of years in which the human body developed according to our lives in a relatively warm environment, which led to the development of an impressive cooling system, but the development of a weak heating system.
The human body, unlike other animals, lacks Organs such as fur, for example, which help it to warm up when necessary.
So one of the first mechanisms in the human body when it comes to heating is an alert system.
Another temperature that we will recognize is skin surface temperature. In contrast to the core heat which is about 37 degrees Celsius, the skin surface temperature is around 33 degrees Celsius (a difference of about 4 degrees).
Our skin is more sensitive to changes in ambient temperature, especially when it comes to temperature decline.
This sensitivity is used as a message system whose function is to inform the brain that there is cooling and it is advisable to start preparing for cold weather.
For example, think of all the times when you were sitting in the room and as soon as you opened a window you felt a chill and a feeling of cold all over your body.
Why? After all, body temperature and even temperature in the room has not changed. This shiver is the body’s way of telling us “I’m getting cold, it’s time to wear something warmer.” If we can not find shelter against the cold, our body activates a heating mechanism, in the form of tremors in the body.
This mechanism of shaking in the body helps the body to extract more heat energy from the muscles and thus warm up.
In fact, this vibration mechanism helps increase the core temperature but because of the inability of the human body to capture the heat generated, and since the tremors affect the normal functioning of the body, our bodies can not survive in cold conditions without external help of clothing or external heat source.
The problem of combining heating and cooling mechanisms
When we are in an environment where the temperature is lower than 37 degrees Celsius, our bodies are in a constant cycle of heating and cooling.
Take, for example, a case that we are on a ski vacation and the temperature outside is minus 2 degrees Celsius.
In the first stage, when we climb in the cable railway to the top of the mountain, our bodies that are at rest are exposed to the low temperature around us.
As a result, we will begin to lose heat and eventually even feel body shakings.
When we reach the top we will begin to surf and immediately feel our body temperature rise and if we are dressed too hot it even begin to sweat, that is, our bodies trying to cool down.
When we reach the bottom of the slope we will be wet with sweat, just before we are about to climb the cable railway again on the way to the top, which will make the way up even colder.
This time, we’re wet with sweat, we’ll suffer even more from the cold on the way up, so we’ll remember to dress warmer, a situation that will make us sweat even more on the way down, And so on.
This wheel of cold and heat exists all the time and worsens as the temperature around us is lower.
The item that will help us maintain temperature regulation and maintain insulation and proper body heat, is thermal clothing.
The purpose of thermal clothing and how it works
In light of all that has been said so far, it is possible to understand that thermal clothing should do several things simultaneously:
1. Isolation and maintenance of body heat.
2. Temperature regulation and prevention of overheating of the body.
3. Keep our bodies dry.
In fact, we require the thermal garment to do many contradictory activities, in order to preserve our bodies in ideal conditions.
In order to do all this, the thermal clothing comes as a first layer on the body and is actually used as a second layer of skin.
Emphasis on choosing a thermal garment
When we choose a thermal garment there are several parameters that we will examine, parameters that will help us decide how effective the thermal garment will be.
- Cut of the garment
Thermal clothing is used as a second layer of skin, in order to allow the thermal clothing to perform its work as required, it is important that the garment will be attached to the body and follow the outline of the body. The better the garment will achieve this basic requirement, the greater the sense of heat (in fact, significantly reducing the feeling of chills caused by exposure to cold air) and the ability of the garment to soak and sweat and thus move it away from the body will also increase. Expert advice: In measuring the garment it is important to keep the garment tight but not pressing and restricting your movement.
- Ability to absorb sweat
One of the most important things in thermal clothing is the ability to remove sweat from the body. In fact, by removing sweat from the body, the garment will keep the body dry and thus keep the body warm (in general, the drier the body is, the warmer it will be). Today there are many materials used in thermal clothing including wool, polyamide, polypropylene, polyester and more. Each of the materials has a different absorbability of sweat, but different manipulations and different structure of the fabric performed by the various urges increases the ability of the fabric to absorb the sweat and move it away from the body.
- Ability to evaporate sweat
After absorbing the sweat and removing it from the body, we will want to soak the sweat and thus remain dry. To make this process possible, thermal clothing makes use of body heat. Our body heat acts as a motor that helps push the sweat away from the body to the outside of the garment. On the outer side of the thermal clothing, a process of sweat evaporation takes place, allowing, on the one hand, to remove excess heat from the body (in the process of drying and evaporation of sweat), while keeping our skin dry and maintaining a sense of warmth.
For this purpose, thermal clothing is used again in materials such as polyamide, polypropylene, polyester, etc., which in combination with a special fabric structure leads to the fact that a drop of sweat will spread over a large area, thus increasing the drying rate of the garment. In thermal clothing at a particularly high level, a combination of water-absorbing material (Hydrophilic) on the outside of the garment and a water-repellent material(Hydrophobic) is found on the inside of the garment. This combination will increase the movement of fluid on the inside of the garment to the outside thus increase the rate of sweat evaporation.
- Insulation ability
The thermal clothing is used as the first layer of insulation. As such, we will want to adjust its insulation ability to the nature of the activity and to the ambient temperature. Today there are many types of fabrics that provide different insulation capabilities and attention should be paid to the insulation ability of the fabric in relation to the thickness and weight of the fabric. As a rule of thumb, you can say that the thicker the garment, its ability to absorb and evaporate the sweat is reduced. If we are going to be active (which means a large amount of sweat), it is recommended to wear a thin garment that will keep our skin dry.
On the other hand, the more passive the activity to which we go (ie, sweating in low quantities), we can give up the ability to absorb and sweat of the garment and focus on the isolation ability of the garment.
- Pleasant to the touch
The thermal clothing is attached to our bodies all day long. One of the parameters to consider is how comfortable the garment is. If the fabric of the garment is scratched or rubbed, it will not be long before you want to remove it. Needless to say that a garment in the bag, no matter how technologically advanced, will not keep your body warm.
One way to identify better thermal clothing is by weight. Thermal clothing as it becomes more professional will be lighter and it is due to the fact that it is made simply from air. In fact, the volume of thermal clothing is about eighty to ninety percent air. The low weight of the thermal clothing is what enables the ability to isolate, conduct and evaporate sweat at a high level. But even before, the low weight of clothing is the one that makes it comfortable to wear and act as a second layer of skin.
- Prevents bad odors
The thermal clothing is constantly absorbing and evaporating sweat, creating fertile soil for bacteria that produce bad odors. In order to deal with the bad odors, we will look for fabrics that have the ability to prevent bad odors, for example, polypropylene. In addition, the higher the quality of the garment and evaporates the sweat at a faster rate, the greater the chance of bad odors being reduced.
- Easy to clean
One of the items that are close to our bodies during the long trip is the thermal clothing. The longer the washing and rinsing period of the garment, the less the temperature regulation of the garment will be reduced. A thermal garment that will be easier to clean will ensure high performance of the garment and will also allow us to obtain a lower quantity of thermal shirts and pants for the duration of the trip.
- Small packing
During the trip, additional thermal clothing is carried in the backpack or suitcase. The size of the thermal clothing package will have a direct effect on the size of the backpack or suitcase used.
Use of thermal clothing in extreme cases
Many models of thermal clothing can be found and most custom clothing is divided into two groups:
- Active clothing – Designed for use when we are engaged in activity that produces a lot of sweat in a bit cold to cold weather.
- Passive clothing – designed for use in extremely cold conditions when we are in an activity that hardly produces sweat.
In addition to these two groups there are additional types of thermal clothing for more extreme situations:
- To a situation where we want to combine active and passive, that is, in case we do not want to change a shirt before we increase the pace of activity, a thermal garment that incorporates a zipper in the chest area, a zipper that allows you to increase the ventilation capacity of the shirt as the body temperature increases.
- When the ambient temperature is cool and we engage in a particularly intense activity, we can also find short thermal clothing.
- More advanced thermal clothing, using the technology of body mapping. This technology uses the knowledge that each area of our body produces heat and sweat in a different quantity and requires a different level of insulation and conductivity and evaporation. Using this technology makes it possible to produce a shirt suitable for use in a large range of temperatures and activity levels.
Finally, remember, any thermal clothing, good as it may be, may not be able to evaporate the amount of sweat your body produces. In such a case, it is recommended to stop and rest or reduce the intensity of the activity to the level where the garment manages to cope with the amount of sweat created.
Protection and treatment of thermal clothing
Thermal clothing is usually made of synthetic materials with a tendency to shrink. When we wash or iron thermal clothing, it is very important to pay attention to the laundry instructions attached to the product, in order to prevent damage to the garment.
It is recommended to ask the sellers about how to wash the garment you chose.
We hope we helped you to understand how does thermal clothing work and how you should choose one.
If you have any comments please leave them below.
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