Here at OutdoorGearLab, we know what you might be thinking: what makes underwear travel underwear? Basically, travel underwear is meant to move. Usually constructed with synthetic materials or wool, travel undies are designed to combat moisture and odor while keeping us comfortable day after day. They need to be flexible enough for different activities to help you slim down your suitcase or backpack, while also being light enough to bring anywhere. In this article, we explain these traits to help you navigate the market.
Let's Talk About Cotton
Of the many pairs of undies test in this review, none of them is cotton. And that is intentional. Cotton has a few major downsides for active use: it's slow to dry, generally less durable, and can have a tendency to stretch out after use.
Because our underwear has significant skin contact, any sweaty activity is going to force your cotton undies to absorb quite a bit of moisture. Cotton can be breathable, but it's generally not going to wick moisture away like some synthetic materials. And because we generally wear our underwear under other garments, they can take a long time to dry. Wet underwear = cold, wet skin, which can be a major issue in the backcountry without the option to change.
On top of this, getting your cotton undies damp will cause them to stretch out, and if you're committed to the same pair for multiple days, whether you're on a backpacking trip or long flight around the world, this could cause discomfort and chafing.
On the other hand, cotton has a few great qualities. It's breathable and natural, which is why some gynecologists suggest cotton for women's undergarments. Great for everyday use, they just aren't our recommendation for travel and active use.
So, What Should I Do?
After months of testing, we learned that travel undies definitely have their place. But so does cotton. Our favorite travel method is a combination: we wear our fancy travel undies all day and then swap them out for a pair of loose, cotton underwear at night. We find this to be the best of both worlds, both from a health standpoint as well as a price standpoint. Since the average price of products in this review is nearly $30, we also know that many of our readers may just pick one fancy pair and stick with it. So which one should you pick?
Synthetic vs. Wool
We tested products made of merino wool and synthetic materials. The synthetics mainly consist, singularly or in a combination, of nylon, spandex, lycra, and polyester. All materials have their pros and cons. Our Editors' Choice Award winner, the REI Co-op Active Bikini is made of a polyester/Spandex blend, while our Best Buy Winner, the Under Armour UA Pure Stretch Hipster, is nylon and Elastane. We also included a Top Pick for Wool, the Smartwool Merino 150 Bikini, which is constructed with an 87% merino wool and 13% nylon. Not sure which direction to go? Let us explain some of the differences between natural and synthetic fibers.
Synthetic materials like nylon, Spandex, Lycra, polyester, and Elastane are manufactured materials that excel in activewear. They are generally very good at wicking moisture and drying quickly, two incredibly important characteristics in travel underwear selection. They also can be quite durable, usually more so than wool or cotton. Lycra, Spandex, and Elastane are often included in underwear and base layers to incorporate more stretch into the garment, which is one thing we really liked about our favorite undies.
On the flip side, synthetic materials are known for their odor retention. Long gone are the days of permanently smelly undergarments, however. Most of these garments included some form of added odor prevention. Odor buildup is caused by bacteria that accumulate in the material when it becomes saturated with perspiration. In order to prevent this moisture buildup, manufacturers have started including treatments to their garments designed to prevent this odor-causing bacteria from being able to grow. During our months of testing, we didn't notice any odor buildup in any of the synthetic undies we tested, but if odor control is one of your chief concerns, you may want to avoid synthetic materials.
Natural materials like wool can make for excellent base layers and undergarments. Each wool garment we tested has a unique texture and fit. Wool is especially good at odor prevention as its natural fibers are inherently odor resistant. Wool is better at wicking moisture than cotton, but usually not as good as most synthetics.
One problem with wool is that it takes a bit longer to dry, which we found to be true in our drying time tests. That being said, the thinner merino wool seemed to be comparable to slightly thicker synthetic materials, so this may not be a significant enough difference to change your purchasing preferences. The last problem with wool is that, in general, it's not as durable as synthetics. While our months of testing were not enough to cause any visible wear-and-tear to any of these products, we'd fully expect to have to retire the wool pairs first, even if it is years down the line.
Finding the One
To begin this review, we did hours upon hours of research. We compiled data on forty of the country's most popular products, comparing their rankings and ratings at a variety of retailers. Out of these forty, we picked the nine most compelling products, looking to span a price range and to include a variety of material types. Once we had all nine products in hand, we started testing. Our team spent months wearing these products everywhere, from the alpine wonderland of Argentine and Chilean Patagonia to the jungle crags of Cuba and back again. Through this process, we identified four of the most important qualities in a pair of travel undies and used these metrics to judge each product against its competitors. Here, we'll explain what these four metrics are, how to use the scores in each category to make purchasing decisions, and what you might do differently depending on your individual needs.
Our underwear has more skin contact than nearly any other product that we wear, so we knew right away that comfort would be important. What we learned was that this can take a variety of forms. We decided on a few traits that would help us come up with an overall score for comfort: softness vs. itchiness, material thickness, and breathability. Originally, we had included fit in this metric, but we realized fairly quickly that this review would be more comprehensive if we awarded different scores for comfort and fit, so we broke them up into separate scoring metrics.
The first thing we looked at, and the first thing we think you should look at, is how soft the material is. This is a bit subjective, so we highly recommend checking out these products in person before purchasing. Overall, we awarded the highest scores for products that had a silky smooth feeling. Thickness varied, but overall, we liked the thinner materials better. Breathability was a huge part of this category.
Of the eight products we tested, the ones that scored the highest in comfort were the REI Active Bikini, our Editors' Choice Award winner, and the Patagonia Barely. Each product's comfort score was 30% of its overall score, but if you're traveling in particularly hot and humid climates, we might pay special attention to products that scored highly in this metric. Other super-comfortable products were the Patagonia Active, Smartwool Merino 150, and ExOfficio Sport Mesh Hipkini, all of which are very breathable, soft, and feel great on the skin.
As we mentioned above, our testing team separated fit from comfort. A product's fit score describes its shape and size, as opposed to its comfort score which is based around the materials. To come to a score about fit, we looked at the sizing, seams, waistbands, leg openings, stretchiness, cut and-- yes, we'll say it-- wedgies.
So many things have to come together for a product to get a high score in this category. It needed to be stretchy without compromising security, and it had to provide coverage without sacrificing comfort. But the biggest test was the wedgie test. We ran, biked, hiked, practiced yoga, and climbed trying to get these undies to shift around on us. Some were instant wedgie makers, while others stayed in place no matter what we did.
In the end, the highest scorers were ones that included a decent amount of stretch while including leg openings snug enough to keep the garment in place. The Patagonia Active, ExOfficio Give-N-Go, and REI Active were the three highest scorers for fit, with the Patagonia Barely close behind. While the Smartwool Merino 150 had a wedgie-free design, the lack of stretch prevented it from being a finalist in this category. Fit is incredibly important, and if you plan to take these undies on the move during vigorous activity, we can't stress enough how badly you need undies that stay in place. If you're looking for a product to accompany you on your biggest adventures, we'd look at this metric first.
Next up on our list of tests was drying time. This was a much more objective metric than the two mentioned above, and to find the results, we conducted simple experiments: we soaked each product in water and hung them to dry! We tried hand-wringing them and towel-drying them first to see if we could shake up the results, but we generally found the same drying times no matter what method we used.
This metric will be of the utmost importance to you in a couple of different scenarios. If you know that you'll be on the go, washing your undies in the sink or nearest stream, you'll save a lot of time by choosing a quick-drying product. Additionally, if you travel in hot or humid climates or know that you're likely to work up a sweat, those would also be great reasons to pay close attention to the highest scorers in this category. The fast-drying products in this review were the REI Active, Smartwool Merino 150 and Under Armour Pure Stretch. Of these, the REI Active is by far the most comfortable, while the Pure Stretch was our Best Buy Award winner and is less than half the price of the Merino 150.
Finally, we've come to packability. This metric is used to describe how easy it is for us to bring each product along on an adventure. The two factors to this category were weight and compactness. This was also one of the more objective metrics in this review. We started by putting each product on our own scale in order to compare each pair of underwear against its competitors. We then folded each pair the same way and looked at them side-by-side to compare which were the thinnest and which carried more bulk.
We have to stop here for a second: the range of weights in this review was from .6 ounces to 1.4 ounces. While this might seem like a big range, we're talking about fractions of an ounce making the difference between products. And even the "bulkiest" of the undies was still surprisingly compact and easy to tuck away into our already overstuffed suitcases. Because of this, packability is only worth 10% of each product's overall score. We strongly suggest using this metric as a secondary deciding factor, after you've narrowed down your options of the three more important metrics described above.
All of that being said, there were some obvious winners here. The REI Active Bikini was the lightest at .6 ounces, closely followed by the Pure Stretch and the Merino 150 at just .7 ounces apiece. Next up we had the Patagonia Barely at .8 ounces, and the Patagonia Active, at .9 ounces. All of these options are incredibly lightweight, and because their weight difference is only noticeable on the scale, not on your body, we recommend shopping first by the other metrics and then using this category to narrow down the selection.
These Undies Cost How Much?!
We know, we know: these products probably cost more than you're used to spending on underwear. And to be honest, our lead tester spent years doing all her big objectives in the same one pair of synthetic undies because it felt like too much of a splurge to have multiple pairs. We hear you, and if this is how you're feeling, we have a solution.
No, we don't think that travel underwear is necessary for everyday wear, but we do think it makes a big difference for long missions in the mountains or for extended trips. Because you might just invest in one pair, we'd like to talk a bit about cost. First, however, we should emphasize again that the comfort and fit of each product may differ a bit from person to person, and we highly recommend trying them on before purchasing. Additionally, if you're only going to invest in one pair, we might put a higher emphasis on durability by choosing a synthetic material which is typically longer-lasting than a wool one.
The price range of products in this review was between $12 and $40, which is quite the spread. The $12 pair was the Under Armour Pure Stretch. This product received high drying time and packability scores, with a decent comfort score and an average fit score. If you're looking for a simple synthetic product for days when cotton just won't cut it, this is a great place to start. That being said, our Editors' Choice Award winner, the REI Co-op Active Bikini, is priced at $17, not much more than the Best Buy. We think the Active is a better all-around product and is easily worth the extra $5. And while the Smartwool Merino 150 is a bit more expensive at $30 per pair, this is hands-down the best wool model in this review and, coincidentally, also the least expensive wool model.