The article has been broken into 2 parts:
Hiking and backpacking safely is largely all about moisture management. We spend inordinate amounts of time figuring out how to keep moisture out of our packs (i.e. pack liners), off of our sleeping gear (i.e. shelters), off our backs (i.e. rain gear), and in our bodies (i.e. water treatment and hydration). In fact, if it weren't for moisture management, I would hazard a guess that 95% of the outdoors industry would be largely unnecessary. Ok, maybe 95% is a bit of an exaggeration but you probably get my point.
In this two part article series, we are going to discuss a moisture management strategy for a body part that we often don't give much attention to: our legs. More specifically, the use of tights as a backpacker's tool for comfort and moisture management in all (or most) seasons. Yep that's right, tight pants. I can see a lot of you men cringing already.
Hiking in tights.
A lot of my research into backpacking clothing and gear can be credited to my wife Renee. Early on in our hiking/backpacking days she was reluctant. She had fears of being cold, wet, and uncomfortable. If I wanted to have her joining me on crazy outdoor adventures, I needed to figure out systems that work. While she is able to grit her teeth and push through some discomfort if she has to, she also encourages me (ok, maybe complains is a better word!) to figure out how we might be able to improve our systems when we encounter adverse conditions.
One condition we have been working on improving is backpacking in wet and damp conditions. Living in eastern Canada (after having moved from the eastern US) wet conditions are no stranger to us. Learning how to be as comfortable as possible in those conditions means we can get out more often and even enjoy it too.
When it comes to rain, backpackers spend a lot of time discussing waterproof shells for their upper body. Generally, they don't however spend a lot of time talking about their lower bodies. Most backpackers belong to one of two camps: either they wear waterproof pants or they don't (disregarding the few who wear chaps or ponchos). My wife and I belong to the camp who doesn’t wear waterproof pants, as we find them way too hot and sweaty.
While avoiding the use of rain pants helps, it isn't always a comfortable situation. When the air is cool and wet, having wet pants can be chilling. The wet fabric when exposed in the air becomes cold, and then when it brushes against your warm leg it feels chilly. Having wet loose fabric draped around your legs is just generally not a pleasant feeling, especially when the rain is coming down hard. If conditions are cold - as can be found in the shoulder seasons - being cold and wet can lead to undesirable circumstances.
The Theory of Drying
Before we talk about tights and how they potentially solve some of these problems, let's first talk about drying.
The act of drying is really just a transfer of moisture from something with high moisture content to something else with lower moisture content. In the case of clothing, the thing with the high moisture content is the fabric, and the thing with the low moisture content is the air.
The amount of moisture the air can hold at any given time is affected by temperature. The higher the temperature, the more moisture the air can absorb, and the lower the temperature, the less moisture it can absorb. Relative Humidity (RH) represents the how close the air is to its moisture capacity for a given temperature. 100% RH means the air cannot absorb any more moisture. At any given moisture content (say 50%), if the temperature rises the RH will decrease (the air's capacity for absorbing moisture increases), and if the temperature falls the RH will increase (the air's capacity for absorbing moisture decreases). If the temperature continues to fall until the RH reaches 100% then dew (condensation) forms. That temperature is called the Dew Point.
Now back to drying. How quickly a piece of clothing will dry thus depends on the RH of the air. When the sun comes out the air warms up (the temperature increases), and the air can hold more moisture. As a result things will tend to dry faster (unless of course conditions are both hot and humid). As the ambient temperature cools drying can take a lot longer.
One significant source of heat that can also affect drying is body heat. Our bodies warm up the air around our clothing, and thus the RH of the air in that "microclimate" drops. The air is able to absorb more moisture (hence, dry quicker). That is also why close fitting clothing dries quicker than loose fitting clothing: the looser fitting the clothing, the slower drying it is because your body is unable to warm up the air surrounding the fabric.
Aside:Another factor in drying is air movement. When a piece of clothing dries, the air directly surrounding the fabric starts to become saturated with moisture (especially when it already has a high humidity). In the absence of air movement, at some point that air will not be able to absorb any additional moisture, and hence drying will slow significantly. If the air moves - via wind, walking, etc. - drying is able to continue at a steady pace because the air surrounding the fabric doesn't have a chance to become saturated.
Aside:I have never understood the purpose of a loose fitting base layer. The real reason is probably one of fashion. Many people will feel that a snug fitting garment is not flattering, and thus will opt to wear something baggier. We wear base layers for moisture and thermal management. If the garment is not form fitting, then we really do not maximize the benefits of moisture management or thermal regulation. Many professional cyclists will even wear a base layer in very warm conditions simply for wicking. The closer fitting the base layer, the better it will perform.
Tights - long the staple of runners and cyclists the world over - haven't really made much headway into the backpacking world, but actually have a lot to offer it. They excel at wicking moisture due to being close to the skin. They dry quickly due to being close fitting. In wet/rainy conditions, they kind of behave like a wetsuit.
The theory behind a wetsuit is that the moisture is held against your skin and acts as an insulating layer. The water on the outside may be cold, but the water against your skin is warm and provides a barrier to cold transfer. Tights work in a similar way. In wet conditions, although your legs may be wet, the layer of water against the skin is kept warm by your body heat. If your legs continue to get wet via external moisture (i.e. precipitation), the cold is buffered by the insulating layer against your skin. Thus it is less of a shock to the body and therefore you are more comfortable. Because tights are much thinner than a wetsuit, and don't have as much of a resistance to moisture traveling through them, they are not as effective or efficient. That being said, they are much more comfortable (thermally) than loose fitting pants of the same thickness.
Ok, now that we have gotten through the theory, how do they work in real life? When my wife and I first embarked on this article project, neither of us had used tights for hiking or backpacking. We wanted to conduct an experiment. We wanted to try out a bunch of different brands and models to figure out what worked and what didn't, and see how tights might fit into a backpackers toolkit. What follows is our observations after almost a full year of testing.
On the trail and staying warm.
What We Like About Them
There are all kinds of brands, models, and concoctions in the tights world. These are generalizations of what we like, not specific to any particular model. Part two will get into the specifics about tight fabrics and construction.
- We are more comfortable in precipitation. Not having floppy wet fabric against the skin when it is raining feels really nice. We also feel warmer.
- They provide great freedom of movement. The stretchy, unrestrictive nature of the fabrics used feels liberating.
- They can be a multiple use item, functioning as both long underwear and tights. If you are going to bring a pair of long undies, why not bring a pair of tights instead?
Generally, Renee and I have come to prefer wearing tights in the "other" three seasons (i.e. fall, winter, and spring). Especially conditions/locations where the air is going to have the tendency to be cool and damp, or wet - conditions in which getting wet has a higher likelihood of being uncomfortable. In the summer, it is kind of hit-and-miss, depending on the conditions.
When Tights Don't Work
- Bugs: While we found tights work fine for noseeums (midges) and blackflies they don't work so well with anything much bigger. Ticks shouldn't be a problem either (although we don't have many here where we live). Mosquitos, horseflies, etc., all the bugs who have no problems working through a thin layer of fabric will generally not be hindered by tights. In those conditions, tightly woven thin nylon fabric pants work much better.
- Thorns and brush: If you are going to be doing some heavy bushwacking or traveling in areas with big sharp thorns, then tights won't be a great option. They will not provide the protection you need, and they will have a much greater tendency to snag. That being said, if conditions allow for a thin windshirt or sil-nylon pack, then a pair of tights should hold-up just fine.
Why Don't More Backpackers Wear Tights?
After having experienced good success with them, I am more or less sold. Why aren't others? Why don't we see more tights in the backcountry?
One reason I can think of is fashion. Tights aren't fashionable in the backcountry. Actually, women don't mind it so much, I see women wearing them more often than men. In the era of Bear Grylls with big knives and burly nylon pants packed with pockets, tights don't fit the stereotypical outdoorsman image. Of course the fine readers of BackpackingLight wouldn't necessarily fall into that category, as one of the main the reasons you are here is because you are looking beyond the mainstream.
Another reason might be modesty. Perhaps people feel self conscious of their bodies and would rather hide behind something a little baggier. For people who might be self conscious with wearing them, pairing tights with a pair of lightweight shorts can be a good option. It adds a little more weight and hinders dry time somewhat, but adds durability, a little more wind protection and leaves more intimate details to the imagination. In fact, instead of bringing a pair of long underwear and a pair of pants, why not try bringing just a pair of tights and a pair of shorts? We have found that to combination to work quite well.
Perhaps durability is the third reason. If you need to do some heavy bushwacking in nasty/thorny conditions, then yes, tights won't be the best option. In many conditions, especially on-trail, durability won't be an issue.
Stay tuned for part 2 of this article where we will discuss several brands/models of tights that we have tested.