Core Backpacking Clothing || Go Suit — Item 5-6: Pants & Underwear

The obvious choice for bottoms when faced with cool temps, heavy bug pressure, thick brush, and/or intense sunshine is a pair of pants and underwear.

The obvious choice for bottoms when faced with cool temps, heavy bug pressure, thick brush, and/or intense sunshine is a pair of pants and underwear.

In temperatures too cool for running shorts (less than about 50 degrees), I wear hiking pants and underwear. Probably more often, however, I wear pants only to protect my legs from brush, sun, and bugs. In these instances, the additional warmth of pants is actually a liability.

Pants and underwear are Items 5 & 6 of the Core 13, a 13-item collection of backpacking clothing that can be mixed-and-matched to create appropriate clothing systems for every set of 3-season conditions.

Pant fabrics

The intended application will dictate the optimal pant fabric weight, fiber, and treatments. For cooler temperatures and really intense bushwhacking, a heavier woven nylon fabric is preferred. But if the pants are merely for sun, bugs, and mild brush, a lighter polyester — which will have less durability but better moisture management — would be more comfortable. A permethrin treatment is a must for lighter, loosely woven fabrics during peak bug seasons.

Pant fabrics with a small spandex content (5-10 percent) will offer better stretch and fit, but they will be heavier, absorb more water, and dry more slowly. Pants treated with DWR (durable water repellant) will shed some precipitation when new, but the treatment will quickly degrade due to abrasion, dirt, and body oils. In fact, after a few weeks of use there is no difference between pants with or without a DWR treatment.

Pants are an obvious choice for cold temps. But they may be required too in warm or hot temps due to intense sunlight or bugs. In those circumstances, the ideal pants would be as airy and cool as shorts.

Pants are an obvious choice for cold temps. But they may be required too in warm or hot temps due to intense sunlight or bugs, or light brush. In those circumstances, the ideal pants would be as airy and cool as shorts.

Pant fabric closeup. Woven cotton/polyester blend (left) and stretch woven nylon (right)

Pant fabric closeup. Woven cotton/polyester blend (left) and stretch woven nylon (right)


For underwear, I prefer boxer briefs made of lightweight polyester or nylon with a small spandex component (5-10 percent) for improved fit and stretch. Merino wool boxer briefs are available too, but I prefer the superior moisture management of synthetics for this application. Indeed, this is an area prone to odors, and polyester only makes it worse, but I rarely notice: my underwear is 3 feet from my nose and trapped beneath my pants.

By replacing Item 4: Running Shorts with tight shorts or compression shorts, which could also double as underwear, the Core 13 could be reduced by one. However, I would discourage it since the optimal fabric weights for these items are different:

Gosh, am I really putting photos of my underwear online? Looks like it. But I suppose others post even more personal things.

Gosh, am I really putting photos of my underwear online? Looks like it. But I suppose others post even more personal things.

Fabric close-up. All are a synthetic fiber (polyester or nylon) with a small spandex component for improved fit and stretch. The green boxer briefs are woven, and they have noticeably less airflow than the other models, which are knits.

Fabric close-up. All are a synthetic fiber (polyester or nylon) with a small spandex component for improved fit and stretch. The green boxer briefs are woven, and they have noticeably less airflow than the other models, which are knits.

My picks

RailRiders Eco-Mesh Pant. If I had to settle on a single pair today, these would be it. The specs are very attractive: permethrin-treated, lightweight nylon without any spandex, and wide mesh vents for enhanced airflow in warmer and more humid conditions. They are baggy, which makes them sloppy-looking but which further improves air exchange.

RailRiders only sells direct. If you want to visit a local outdoor retail store to try on various pairs, look for pants such as the Marmot Torrey Pant (stretch) and Mountain Hardware Mesa Pant (no stretch).

Sierra Designs DriCanvas Pant. I take these on all trips in warm or hot temperatures when little or no precipitation is expected, e.g. the Desert Southwest, or California or the Rockies during an inactive monsoon. These pants are tough and very breathable, and they fit me well. But if you only want one pair of pants in your collection and you sometimes backpack in wet parts of the world, go with a pure synthetic pant instead.

Suitable underwear is widely available:

My own underwear inventory came from a local Jockey outlet store; try the Seamfree Boxer Briefs or Microfiber Boxer Brief.

Sierra Designs DriCanvas Pant (left), which are my go-to for dry trips only. And an old pair of Salomon stretch woven nylon pants (right), which I wear everywhere else.

Sierra Designs DriCanvas Pant (left), which are my go-to for dry trips only. And an old pair of Salomon stretch woven nylon pants (right), which I wear everywhere else.

Posted in on March 15, 2015


  1. Doug on March 15, 2015 at 9:44 am

    Hey Andrew, thanks for the continued advice on clothing selection. I hike in the high Sierra throughout the summer, mostly between July and October. Ive found temperatures range from 20 to 35 at night and 50 to 80 during the day, often very sunny. Usually I have a tent setup in the afternoon when it sometimes rains so I’m not usually hiking in the rain. What do you think of convertible pants options or the long johns under running shorts as options? Do you usually pick one or the other or sometimes bring both?

  2. Joslyn on March 15, 2015 at 11:43 am

    Even when I wear pants, they are running pants. I have no idea who is designing hiking pants, but they are not meant for actual hiking, just looking good on a model.

    • Andrew Skurka on March 15, 2015 at 12:03 pm

      I think designers are taking “pants” too literally. If you ask hikers why they wear pants, they will normally cite protection against sun, biting insects and ticks, and light brush. They rarely say, “Because without pants I would get too cold.” In fact, it’s just the opposite — were it not for the protections that pants afford, hikers would avoid pants because they are too hot for the conditions.

      Based on the pants available in the marketplace — which are often heavy and stiff, and have no airflow besides the inherent air-permeability of the pant fabric — it’s as if designers think that backpackers wear their pants while cutting lumber or rounding-up stock. For an innovative outdoor company that is willing to challenge convention, designing a pant with pant-like protections but short-like comfort could be a huge winner.

      • jpvisual on September 30, 2016 at 5:29 pm

        I also like running pants over “hiking” pants in cooler temps when bugs are not an issue because running pants:

        – Have ankle zips and make it easy to slip over running shorts. They also feel more comfortable than a “hiking pant” / shorts combo.

        – Are better than using a base layer under running shorts because they don’t interfere with the short liner, much more comfortable. It also looks better than wearing a base under your shorts.

        – Are more comfortable to sleep in, more flexible and comfortable in general.

        – Generally lighter weight than “hiking pants” if they need to be carried a lot.

        – They give you the same

        I do like the railriders for when it’s buggy and/or very hot/sunny.

  3. Markus on March 15, 2015 at 1:31 pm

    Hi Andrew,

    great set of articles! And just at the right time, as I am currently completely overhauling and decluttering my clothing system. A lot of great info and ideas!

    I have one question though: How do you decide if the expected sun is enough to warrant taking a pair of full-length pants? Do you have any objective way to decide, or go by gut feeling according to your pre trip route assessment?

    • Andrew Skurka on March 15, 2015 at 10:33 pm

      No single objective measure, even though I think I have seen a cloudiness map somewhere in the US Climate Atlas. Instead, I consider a few more relevant factors:

      Shade, which is a function of vegetation
      High-noon sun angle
      Surface reflectivity, e.g. snow

      With bottoms, I normally make my pants/shorts choice weeks in advance. But sometimes it can be a last-minute decision, too. If you were expecting sunny skies for a trip in Colorado, but the forecast calls for an active monsoon pattern, shorts might be a fine pick since sun exposure will be less than expected.

  4. Randy Martin on March 15, 2015 at 5:41 pm

    One the challenges I have in finding an appropriate hiking pant is finding something that is both durable and breathable. More open weave (breathable) material too often means they tear more easily because they tend to grab onto branches and rock, whereas the tight weave of most nylon pants don’t grab on to things and just roll with the punches so to speak. Of course with the tight weave I tend to give up on breathability.

    So that for me is the dilemma in finding the optimal hiking pant material.

    As for fit, I prefer a looser fit in the legs or else a very articulated cut. Normally the articulated cut adds a lot to the price and so baggy is what the budget allows for.

    • Andrew Skurka on March 15, 2015 at 10:03 pm

      If you’re regularly into thick brush, I think the durability/air-permeability tradeoff is unavoidable to some degree. But it need not be quite so bad: there must be available some tough nylons with better air-perm than comparably tough nylons used now; and perhaps some high air-perm panels could be put in low-abrasion areas like the inner thighs and hamstrings.

      If you’re never into thick brush, or perhaps just every once in a while, the durability/arm-perm tradeoff is inexcusable. There really needs to exist a pant that is designed for the conditions in which pants are often worn.

      • Mitchell E. on March 16, 2015 at 4:47 pm

        I have a pair of North Face Meridian pants that fit the bill in terms of fabric. No ventilation panels, but they’re made of a very light, breathable nylon that’s held up well so far (and I like to beat things up). I live in LA, so it’s almost always shorts weather, but I do a lot of bushwhacking and I’m cursed with very pale, easily burnt skin. The Meridians are the only pants I’ve found bearable in these conditions.

        Unfortunately, it doesn’t look like TNF is making them anymore.

  5. Vadim Fedorovsky on March 15, 2015 at 7:34 pm

    I was under the impression that you primarily used the sierra designs silicone trail pants (woven nylon and spandex I think).

    Is this it true? What’s your opinion on those?

    • Andrew Skurka on March 15, 2015 at 8:22 pm

      I used the Silicone Trail Pant last summer for a week in Wyoming. They fit me really well, and they look sharp.

      However, they are ill-advised for anything beyond low-aerobic activities in cool or cold weather, e.g. hunting in the fall or winter. The silicone treatment on some of the fabric panels significantly increases water-resistance, but entirely at the expense of air-permeability. So they have the very real potential to get uncomfortably hot and stuffy. In fact, they were so hot and stuffy on one 70-degree sunny day in Wyoming that I opened the front zipper in a desperate attempt to get some air moving through. That they are made of relatively heavy stretch woven nylon does not help things — it’d be a hot and stuffy pant even without the silicone.

      It would not surprise me to see this exact pant in a non-silicone version at some point in the future. It’d be a perfect pant for the Pacific Northwest and Alaska, or cooler seasons elsewhere.

      • Vadim Fedorovsky on March 16, 2015 at 7:34 am

        They really are indeed sharp! I can’t stand when nylon pants are “too baggy” and loose. I was originally attracted to buy these b/c of how slim fitting they are…too bad they are not perfect in every way 🙂

  6. Vadim Fedorovsky on March 16, 2015 at 7:36 am

    Andrew in one or two sentences please describe what you think the PERFECT backpacking pant would be. I mean the kind that doesn’t exist yet.

    • Andrew Skurka on March 16, 2015 at 7:49 am

      I think that’s why Sierra Designs brought me on board, isn’t it?

      How perfect do you want to get? Perfect for the conditions you normally see on your trips, in the Northeast, perfect for someone who backpacks in the Desert Southwest, or perfect for any set of 3-season conditions?

      I think I have made it pretty clear what I want to see in a “trail pant,” i.e. pants that backpackers wear in warmer weather because they want the protections of pants:
      * Lightweight fabric with high air-permeability
      * Venting features
      * Permethrin treatment

      For brushy and cooler trips, I think there are plenty of fine woven nylon or stretch woven nylon pants in the marketplace already.

      • AD on February 3, 2018 at 4:08 pm

        Andrew- have you found these pants yet? Or anything close?

        • Andrew Skurka on February 4, 2018 at 8:49 am

          The Railriders Eco-Mesh are closest, but they’re still imperfect. For starters, they’re very sloppily cut, which is made only worse when you open the mesh panel zippers. The pockets and button waist closure need improvement, too.

  7. Philip Werner on March 16, 2015 at 8:05 am

    If you have a pair of lightweight hiking pants that you really like, you can also send them out to Insect Shield and have them treat them with Permethrin that will be good for 70 washings. They’ll treat any clothing for you except shoes. Something to consider.

  8. Dave F on March 16, 2015 at 9:33 am

    I agree with regular pants for bugs and brush, but just for cold I’ve found that long underwear under running shorts works perfectly well to surprisingly low temperatures (I’ve hiked with this setup in the 20’s and have still been comfortable). It doesn’t even need to be something heavy either, I’ve used 120 weight pants and have been fine. It’s obviously not an ideal solution if you expect to encounter lots of abrasion (rock scrambling) or brush, but on open terrain or maintained trails I’ve found it’s actually more comfortable than regular pants.

    • Andrew Skurka on March 16, 2015 at 9:36 am

      Totally agree with you here. BUT, there’s a certain backpacker “look” that I feel oddly compelled to keep, and running rights underneath running shorts just doesn’t do the trick.

      • Dave F on March 16, 2015 at 12:42 pm

        Ha, fair enough. The way I see it, the colder it gets, the fewer people you’re likely to run into… and the ones you will see when it’s cold aren’t the ones who will look at you funny.

  9. Jason Cuzzetto on March 16, 2015 at 9:58 pm

    I have to give the ultimate work, travel, hiking and backpacking pant to the Exofficio Amphi pant. I have worn some version of these for at least 10 years would be my minimal guess. I have worn them as my main go to pant, layers included from French Guyana to Canada, Iceland, Russia, Kazakhstan in all types of weather paired with layers. I have always been able to get away with different weight long underwear, the pants, and a shell pant, like Sierra Designs to using them like swim trunks in the jungle or desert. On occasion I have ripped a pair out, snag something during an airfield operation or climbing rigging to secure something (thank you Tenacious Tape). But whether I am swimming in the Miami River (don’t ask), or conducting freezing airfield operations. They always dry quick, articulate in all directions well, and can look good going to work or dinner. My favorite is they are light and have at least, depending on the year, one zippered pocket with a stylish flap that let me keep my passport and other valuables handy. Trust me, I have lost these same things with other pants. I am going to guess I went through about 8 pair and still use 3. 1 is one of the originals and has lots of Tenacious patches. Just my two cents that it is a great pant to look at. I hate zip offs and love that they offer this without. Thanks.

  10. Adam on March 17, 2015 at 12:33 am

    Thanks for the very informative post.

    For anyone looking; pure merino wool briefs that are not boxer briefs are kind of hard to find. Smartwool has some that are high-rise with poor reviews. Icebreaker has the best ones I found:

    • Andrew Skurka on March 17, 2015 at 7:19 am

      I’d be wary of underwear that doesn’t have at least 5-10 percent spandex. Unless it was custom tailored for you, it probably won’t fit right. And even if it does when you first put it on, the fabric will stretch out and won’t tighten back up until it’s machined-washed and dried. I have a few cotton non-stretch boxer briefs and they are for civilian use only, and not because they are cotton.

      • Adam on March 17, 2015 at 8:20 am

        Good point. I really want them to work, so I’ll have to give them a try. If they’re a no-go, poly sounds good.

        I didn’t get notified about your reply; auto reply notifications by email would be handy if possible.

  11. Luke on March 18, 2015 at 1:51 pm

    Thanks for these posts! I’m moving to Cambodia long-term and will need to wear pants frequently for work (less so for hiking unfortunately) but they can be casual. The RailRaiders look really interesting, but hopefully won’t be too dopey with the zips open when I’m outside. Pricey, but the bug treatment is a huge plus (my spleen abandoned my body a while back, so malaria protection is high on my list). Any other pants you’d recommend for breathability alone? The ExOfficio BugsAway SandFly looks promising as well.

  12. Brad on March 18, 2015 at 7:22 pm

    I will agree with the Eco Mesh pants by Rail Riders. I bought a pair for the JMT in 2011 and they have been my go to pants when hiking above tree line where the temps would normally dictate running shorts for me, but the sun pushes me to pants. I had used some lighter Patagonia Nylon pants (Sol Patrol?) and the Eco Mesh pants are much cooler. They do have the MC Hammer look when you have them unzipped though, but it probably doesn’t matter since I am already wearing my dorky looking OR Sun Runner hat!

    BTW – I think the Ex Officio Give N Go Boxers are nylon, not polyester. I like them better than the competition as well.

  13. gdm on April 2, 2015 at 1:09 pm

    Any advice about chafing? I tried hiking in running (split) shorts on a couple long day hikes, and I got some pretty bad chafing. I’ve never had a problem in standard hiking pants. I don’t see myself bringing the vaseline on a mutli-day trip.

    • Andrew Skurka on April 2, 2015 at 1:23 pm

      Chafing here?

      If your butthole, then you need to be better with your hygiene. Give yourself a “monkey butt wash” every other day or so, making full contact with your butthole. Otherwise, it’ll look like you have a money butt.

      If your thighs, then try running shorts with a boxer-brief liner instead of briefs. They’re less common but they’re out there.

  14. Sam Riggle on April 4, 2015 at 9:27 pm

    What are your thoughts on pairing running shorts with UL wind pants? I know a lot of people would rather carry rain pants instead of wind pants, but I always wear running shorts and if I get chilled I slide on my 2.8 ounce Patagonia Houdini wind pants and I’m good to hike on. If raining, I pair my system with a 2 ounce rain “kilt”. In the winter I wear running tights under my shorts and still layer with the wind pants and kilt. This system is quite a ways lighter than carrying rain pants, far cooler than having to always wear hiking pants, and more versatile. But alas, the wind pants are not as durable. Although I have A LOT of miles IN my wind pants and they look new. I actually just got back from a trip on the AT where I encountered highs in the 40’s, super dense fog and mist, with intermittent rain and high winds. While on the move I wore a Patagonia Fore runner SS shirt, Patagonia Houdini Jacket, Hind running shorts and my Patagonia Houdini wind pants and nothing more. Although the “wind suit” wetted out, I stayed warm and comfortable, while if I had worn my Montane Minimus Smock, which I did for a short while, I would have over heated. Once I got to camp I changed into my drop sleep clothes and that was that. But anyways, I’ve rambled for far too long. I apologize. Just wondering your thoughts since I was kind of surprised you didn’t mention that set up.

    • Andrew Skurka on April 5, 2015 at 9:33 pm

      You’ve proven that this system works, so I’d recommend sticking with it on trips with similar conditions.

      However, if you ever backpack in other locations, I think you will discover the limited versatility of your system. For instance, your wind pants would get shredded if you were to ever hike off-trail in even light brush. And if your wind suit were to wet out during a Colorado monsoon while hiking above treeline at 11,000 feet, you would probably take real rain gear on your next trip.

      That is the beauty of the Core 13 — the collection can be mixed-and-matched to create near-perfect systems for any set of 3-season conditions. You might be able to devise a better system for very specific conditions, as you may have done, but those niche products don’t have the applicable range of the Core 13.

  15. Sam Riggle on April 14, 2015 at 1:53 pm

    Thanks for replying. I hope that didn’t sound too snobby or whatever. It’s hard not sounding too critical or elitist without hearing tone of voice.
    But After looking over some of your gear lists I did see that you have incorporated a similar system into a couple past trips. Although you specifically mention bushwhacking it still didn’t cross my mind while I made my last post. Brain lapse. Different circumstances do require different gear.
    And I have no issues with your core 13. I think it’s excellent and spot on. Well done.

    P.s. If you haven’t already, check out the Patagonia Fore Runner long sleeve running shirts. 3.7 oz in a Men’s Small, dries super fast, odor resistant, and UPF 20. Basically like any other polyester shirt, except I haven’t had one this light or cool in the heat. Just throwing that out there.

    Happy trails.

    • Sam Riggle on April 14, 2015 at 7:26 pm

      I guess what I was trying to get to in my original post was that you didn’t mention a system of running shorts and light weight wind pants for certain situations. A long with mentioning wind shirts. I thought it was a more wide spread set up in the “UL” world. I guess these wouldn’t be considered core items though. Especially since rain gear, which I always carry, serves the function of wind protection. That’s what I was attempting to get at in my original post, it just took me three posts to clarify. Great write ups by the way

  16. John on May 25, 2015 at 7:40 am

    For hot conditions, humid or arid, a low-profile swim supporter is the best, IMO, IME. Airflow is excellent, dry time is nil, moisture wicking, and can be layered under insulating pants with no issues.

  17. Sean on August 26, 2015 at 7:05 pm

    I use merino wool compression shorts from Ibex as my underwear, not sure they are still making them though. I love the arcteryx palisade pants. Built in belt, around 10oz, and I have dumped water on them and watched them dry in under 5 mins. My first pair lasted 5 years of decently rough use.

  18. Rene on October 9, 2015 at 11:30 pm

    Hey Andrew. Other than the monkey butt wash every other day do you have any advice on general backcountry hygiene especially in the ‘sensitive’ areas? Seems to be a big problem for my comfort every once in a while when I’m backpacking. Thanks and congrats on the third place finish in the run rabbit run race! Looking forward to more SD Live sessions as well. Have a good one.

    • Andrew Skurka on October 11, 2015 at 8:14 am

      The monkey butt wash does the trick for me so I haven’t needed to experiment with other techniques. Although, it’s been a while since I hiked hard in hot & humid conditions, which are more challenging for this issue.

      For female-specific hygiene advice, you should read this post if you have not already:

  19. Ryan Potterton on February 11, 2016 at 7:42 pm

    Costco has Unionbay Tech Travel Pants for 19.99 which are 94% nylon and 6% spandex. They compare well to similar pants I have which are $60-$90. The DWR is initially very good but I haven’t washed them yet so we’ll see. I like how relatively quiet they are for nylon pants. Noisy pants are my pet peeve and I have returned pants by Kuhl for their “swish, swish”.

  20. PS on March 23, 2016 at 6:54 am

    Hi Andrew, been soaking up all sorts of things from your site lately, thanks for sharing your vast experience with us all!

    Regarding pants: Any experience or opinions with Prana stretch zion convertibles? Seems like it hits most all of your points and might reduce the needed items for your 13 since they are pants & shorts: Nylon/Spandex blend, gusseted crotch, can be shorts or pants as needed. The DWR is not terribly important and assuming either sending in for bug proofing or doing your own Permethrin soak.

    • Andrew Skurka on March 23, 2016 at 8:59 am

      No convertible pants are are ideal as a dedicated pair of shorts (Item 4). They might be okay if you want shorts only occasionally, but I think for any extended wear-time (as shorts) their shortcomings will be well noticed.

  21. Sean McGrath on April 4, 2016 at 9:49 am

    Re. underwear: I used to wear exOfficio regularly, until I read this post and I agree. The Uniqlo Airism are much nicer than exOfficio.

    I use for business travel and wash nightly in hotel (~75 days per year), and I can’t speak about them for backpacking. However, my bet is that they are more comfortable.

    • Josh on July 18, 2016 at 9:01 pm

      I wholeheartedly agree that Uniqlo Airism underwear is great. I make sure to get ones with a standard fly, and I have some in both the standard Airism and also their new Airism Mesh, which is quite simply amazing for hot weather. My recent go-to shirt for anything athletic (mostly cycling for me lately) is an Airism Mesh v-neck. It is also available in a crew neck, but I hate tight collars during the hot/humid summers we get in Ohio.

      I can’t wait to try the mesh tank top, which would have to be about the breeziest thing you could wear and be respectable (if a tank top is considered respectable to you).

      Also, all of these pieces are available for under $10 each if you catch a sale!

  22. Ronnie Spitzer on May 28, 2016 at 7:36 pm

    How about women’s equivalents to the men’s pants? I’ve had difficulty finding pants that are high-waisted (the hip ones get pushed down by my pack), with pockets and reasonable fabrics. Tried your suggested men’s pants but would have required too many alterations.

    • Andrew Skurka on May 30, 2016 at 6:39 pm

      Sorry, don’t make it a habit to try on women’s pants. Maybe some of the female readers can offer some suggestions.

  23. Hunter G Hall on February 7, 2018 at 7:48 pm

    What do you think of these pants:

    They seem unique and Outside magazine recently did a piece on them. Incidentally I can’t determine if this is pay to play or just a legit review of a loved product.


    • Andrew Skurka on February 7, 2018 at 7:52 pm

      I go by the Fjallraven booth every OR show and I never see pants that interest me. The fabrics tend to be thick, boardy, and/or static; and I want a pant fabric that is thin, soft, and slightly stretchy. I think their pants could work well in the right situation, e.g. cool climates with thick brush, and not many miles. Maybe you can get away with them in Washington and for most of the year in the northern Rockies, but I don’t think they’re practical beyond that.

      • Hunter Hall on February 7, 2018 at 9:22 pm

        What about winter backpacking in CA? Overkill?

        • Andrew Skurka on February 8, 2018 at 7:11 am

          I think they’d work better for that.

  24. Hunter G Hall on February 7, 2018 at 7:49 pm

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