Fabric Types

Polypropylene is a material that few people are aware of and even fewer know how to pronounce. But more and more performance clothing manufacturers are using polypropylene as a core fabric in their products. These manufacturers tout polypropylene's ability to keep the wearer warm, dry and comfortable during high aerobic activities such as running, hiking, skiing and snowboarding just to name a few. So what would make polypropylene fabrics an alternative to well known products like Under Armour? Polypropylene, like many other synthetic fabrics on the market today is a polymer or a plastic. This means that it is very lightweight and will absorb little if any water and instead repel water. As a result, polypropylene fabrics dry extremely fast. This feature is particularly useful for next to skin products such as socks and performance underwear. When worn next to your skin, polypropylene will stay dry and helps prevent chaffing and keeping comfortable throughout your aerobic activity.

Another very useful feature of polypropylene is it's ability to retain heat. Polypropylene retains more heat than any other fabric. This means that on top of being very lightweight, thermal underwear made of polypro will be warmer than long johns made of polyester or cotton fabrics.

One of the features I like about polypro is that it typically costs much less than other performance products. I can buy several sets of polypropylene thermals for the price of just one Under Armour thermal top. So the next time you are in the market for some performance active wear, you'll want to check the label to see if it is made of polypropylene.

I've had many people ask me what the difference is between polypropylene fabric and polyester fabric used to make thermal underwear. In this post, I'll point out ony the factors that I think are the most relevant.

First of all, polypropylene and polyester are synthetic materials. They are both polymers, which is essentially plastic. As a result their colors won't fade or bleed when washed because the colors are built into the material. Polypropylene however, is more hydrophobic than polyester meaning that it does not absorb as much water. Since the water cannot be absorbed into the fabric, the water(or sweat) has a tendancy to spread evenly throughout the garment which in turn helps the water to evaporate much quicker than a fabric that absorbs and retains the water. As a quick example, if you cup your hand and put some water in it and continue to hold the water in your hand with your hand still in a cup shape, the water will take a very long time to dry. But, if you uncup your hand and use your other hand to spread the water evenly all over both of your hands, the water will dry in less than 1 tenth of the time.

So, having explained this, polypropylene will dry much faster than polyester. Polypropylene has a much lower melting point than polyester so you will want to avoid washing polypro in hot water or drying it. For this reason, polyester materials are much easier to care for than polypropylene. Polyester is also more UV resistant than polypro. If you wear polypropylene as an outer layer exposed to the sun, eventually the polypropylene fabric will break down and the color will fade. Polypropylene has a lower heat transfer rate which means that thermal underwear made from polypro will retain more heat than polyester.

So really, whether one fabric is better than the other really depends on what it will be used for. If you just need a fabric to wear next to your skin that will dry very quickly and thus keep you skin dry, then polypropylene is probably what you want. If you want just a good all around fabric that also dries quickly, but is very easy to launder and care for, then polyester is probably your best bet.

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Layering for Cold Weather Activities - For many, when the trees shed their leaves, the grass stops growing, and winter sets in, the human hibernation begins. It’s time to crawl into a centrally heated cave, and wait out the cold winter months. After all, without a natural fur coat, humans were never meant to brave temperatures below 65 degrees right?

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For many, when the trees shed their leaves, the grass stops growing, and winter sets in, the human hibernation begins. It’s time to crawl into a centrally heated cave, and wait out the cold winter months. After all, without a natural fur coat, humans were never meant to brave temperatures below 65 degrees right? Their adaptation comes in the form of a small remote that controls the garage door allowing an uninterrupted climate change from the car to the house. However, with the advent of the outdoor retail trade, the idea of turning otherwise harsh winter conditions into a recreational adventure is proving to be contagious. According to the Outdoor Industry Association, major Outdoor Chains combined with Specialty Stores had an estimated $12.3 billion in sales for 2004 with winter sales up 8.5%.

Woman snowshoeing --- Image by © Royalty-Free/Corbis

Now, if you’re a part of that group chipping in to boost winter sales for the Outdoor Retailers, you’re probably spending your hard earned money on gear to help make up where Mother Nature left off. And, when it comes to cold weather, Mother Nature left everything OFF! The problem is, if you’re new to dressing for cold weather activities, knowing what to shop for is only half the battle. Winter gear represents a very diverse portion of that $12.3 billion spent in 2004. This article will help you understand the basics of winter dress and guide you in your selection of the proper attire for cold weather activities.

First of all, the key to dressing for any winter or cold weather sport is LAYERING. Your body has its own heating and cooling system. Layering is a way of maximizing the efficiency of your body’s system. Layering also allows you to adjust to various levels of exertion so that you can maintain a desired comfort range. Layering isn’t a new technique. As far back as the early 80’s the company Patagonia was instructing the outdoor industry about layering through a series of essays presented in their product catalogs. To begin, there are three main parts to layering. The first part is called the base layer which you will also hear referenced as the “next-to-skin” layer. The second layer is going to be your insulating layer. And your third layer is going to be your outer layer or shell.

Your next-to-skin layer is just what it sounds like, an underwear or undergarment that will actually be touching you. This is probably the most critical layer in moderate to high endurance winter activities. As you begin to exert yourself, you sweat. Sweating is your body’s way of cooling itself. Cooling is just fine during warm summer sports, but in cold weather it can actually work against you. Your next-to-skin layer should be made of a material that will pull the sweat from your body keeping your skin dry and comfortable. The process of pulling sweat from your skin is often referred to in the outdoor world as “wicking.” Underwear designed for wicking come in an array of materials, some natural and some synthetic. The first rule of thumb when choosing a next-to-skin layer is to wear anything but cotton. Cotton wicks sweat, but retains it and takes way too long to dry, which keeps your skin wet and cold. 100% polypropylene is probably the best material for the money. Polypropylene underwear does not absorb any water so it dries very quickly. Polypropylene also has a lower thermal conductivity rate than other fabrics, which means that heat is slow to leave the material. Now, there really are too many fabrics and materials to list. If you are really serious about finding out what will work the best for you, I would suggest getting into some forums and researching what other enthusiasts have experienced and what they recommend. Otherwise, just start with the polypropylene. Polypropylene underwear costs much less than other high tech thermals.

Next is your insulating layer. With this layer, you first have to determine how active you will be versus how cold your surrounding temperatures will be. For instance, if you will be snowshoeing(very high intensity) on a cold blustery day, you would probably just want a thin insulating layer just to keep the chill off. But, if you are going to be ice fishing(low or no intensity) all day in below freezing temperatures, you would need a much thicker insulating layer. It is important here to note that the more air a material traps inside of it, the warmer it will be. For this reason, a nice thick fleece top and bottom works very well. Polyester or polypropylene fleece will help sweat move from your next-to-skin layer toward your outer layer. Fleece is also very light weight and because of the design of the fleece fibers it traps a lot of air in the material itself. As a general rule, the thicker insulating layer, the warmer it will be.

Finally, your third and outer layer will provide you with a waterproof, windproof barrier. This layer is referred to in the outdoor industry as your “shell” layer. Like your second layer, the functionality of your shell will depend on what you are doing. If it’s going to be snowing hard on you or if there is a chance that you could get wet, then you would want to have a waterproof shell. If a material is waterproof, then it will also be windproof. One of the problems with most waterproof materials is a lack of breathability. Gore-Tex® and eVent® fabrics are popular waterproof/breathable materials used in high quality shells. While these fabrics are breathable, the breathability is still somewhat limited. These fabrics perform very well during lower endurance activities while performance is moderate at high activity.If you don’t think that there’s a chance of getting wet, then you might opt for the popular “soft shell,” a stretchy windproof fleece shell that is often treated with a water resistant coating to provide additional protection. One of the primary benefits of the soft shell is increased flexibility as well as breathability.

The layering techniques presented here are really meant to provide an awareness of the proper dress system for cold weather. It is important to adapt these ideas to your particular need. Emerging fabric technology is constantly changing the way we dress. You might be surprised to know that many of the fabrics used to make high fashion dress today originated in the outdoor industry. Now, don’t hibernate this winter. Find an opportunity to get out and enjoy the outdoors. If you dress properly, you will stay warm and enjoy yourself no matter what the activity.

How can such a soft, snuggly, comfortable fabric like cotton be so hated among veterans of the high activity sports world? In this post, we'll cover the basics of why cotton is a definite no-no when putting together your wardrobe for any outdoor or otherwise high intensity sports activity.

The first part of the dilemma with cotton doesn't necessarily have to do with cotton. It has to do with you. Your body has a built in cooling system that tells itself to produce sweat when it gets hot. While sweat is great for cooling your body down, it can also cause extreme discomfort if it is able to remain against your skin through the duration of your activity and long after you have finished. And this is where cotton comes in. Cotton has the ability to absorb larger amounts of water than other fibers acting as a sponge when you sweat. This sponge-like feature of cotton does not allow your sweat to dry very quickly. So, after just a short while of hiking up that steep mountain, playing a friendly game of tag football at the park, or even just rowing your canoe across the lake, your cotton clothing will begin to get wet with sweat, soggy and very uncomfortable. If your activity lasts for an extended period, then the problem doesn't stop there. Remember when you were little and you would play around in the pool long after your mom told you to get out and your hands and feet would start looking like prunes? That very same thing happens within your cotton socks and clothing often causing chaffing and more discomfort.

Now, let's say that you are finished with whatever sport it was that caused you to sweat so profusely. Let's also suppose you don't have a locker room to change in and going home is not an option either. Your cotton underwear, cotton shorts, cotton socks and cotton shirt are no longer the warm, cuddly garments they used to be. Cotton is not able to retain heat very well when wet. You're now stuck in wet clothing with a drying out time ranging from hours to possibly days. For you, this might only mean a short period of discomfort. However, if you are going to be somewhere overnight or even for a few hours where the temperatures are around 50 degrees or lower, your wet clothing can become a killer. Many hypothermia deaths are caused by wet clothing in mild to cold temperatures. Your body just can't warm itself quicker than your wet cotton clothing cools you in colder temperatures. That's almost a tongue twister.

Until fabric companies really started digging into the whole science of fabrics, there really weren't many options. So the outdoor sports participants, team sports players, joggers, and anyone else who sweats just had to suffer through all of the downsides that cotton has to offer.

Summary:

Cotton retains water, dries slowly, and does not keep you warm when wet so it is not ideal for high endurance activities that involve sweating.

Tips:

1. Take all of your 100% cotton clothing that is supposedly for outdoor sports or athletic activities and donate it to your local charity.
2. When you're at the meeting for your first winter klondike receiving instructions on the dangers of such an activity, don't raise your hand and ask how many pairs of COTTON thermals they would recommend you bring along.
3. If you have an annoying inlaw that is really into hiking, backpacking, outdoor sports, etc., make sure that the clothing you give them is 100% cotton and tell them it is for their next trip.