Xero Kelso Shoe Review
The Xero Kelso is a foot-health-positive minimalist shoe that seamlessly blends sporty style with formidable function. Known for their ultraminimalist approach... Read more
Founded in 2009 as a small, boutique company manufacturing DIY sandals, Xero Shoes has since become an industry staple in the minimalist footwear market, producing a wide variety of ready-made sandals and closed-toe shoes and boots in both the athletic and casual footwear spheres. With the thoughtfully designed HFS, Xero has shown how attention to detail can improve barefoot-style running and athletic shoes, providing an option for both competitive and non-competitive athletes alike. Built upon a back-to-the-fundamentals, zero-drop platform that helps promote foot/ankle stability and a more natural gait, the Xero HFS boasts an abundance of design features that serve to improve performance and comfort. For users of this shoe, this also represents an opportunity to make foot and musculoskeletal gains in a variety of contexts. The Xero HFS, then, not only checks all of the boxes for optimal foot function, but it also provides performance features that set it apart from other athletic shoes we’ve tested.
Read on for our full review of the sporty Xero HFS (and HFS II)!
Before we get rolling with this Xero HFS shoe review, though, an important caveat: In this article, we are reviewing the men's version of this shoe, which is what we recommend all users purchase (to ensure maximum toe box width). More info about men's vs. women's models and sizing suggestions for all will appear later in this article.
While the Xero HFS has a range of technical features, we’ll start by covering the basics. Here are the three most notable design features we've identified in this foot-friendly athletic shoe:
These important design inclusions, found readily in the Xero HFS, form the foundation of a truly foot-healthy shoe, and they help ensure that your foot will be able to perform at its best in an accommodating and comfortable environment. Let's now turn our attention to some of the other interesting and unique features of the Xero HFS, a shoe that athletes and active individuals of all kinds love for its technical features and ability to support the foot in a natural way.
As mentioned earlier, the Xero HFS is jam-packed with advantageous design features that promote optimal foot form and function (instead of trying to dictate foot shape, position, and performance, like many conventional athletic shoes) and is thoughtfully constructed to ensure that you get the most out of them. Some other unique features of the Xero HFS, then, include the following:
Overall, the Xero HFS has technical features that make it an ideal ultralight running and athletic shoe, sparing you the unnecessary features found in conventional athletic footwear that add weight and bulk and negatively impact the user experience.
SHOP XERO HFS SHOESClearly, the Xero HFS is designed as a road running and walking shoe, and it truly excels in this realm. The HFS's lightweight build makes it suitable for racing, too, and it’s also well-equipped to be your go-to trainer. As with most foot-healthy minimalist athletic shoes, the HFS can be used for a variety of other movement-based activities, including tennis, squash, racquetball, pickleball, gym workouts, and fitness classes of all kinds. The flat, thin, and flexible sole of the Xero HFS enhances the experience of body-weight training in particular, and if you forget your casual shoes or simply want to be out and about in something more breathable, the HFS can accompany you virtually anywhere your day might take you. The ultralightweight nature and foldability of the HFS also make it a great travel shoe.
The Xero HFS is a true ultraminimalist athletic shoe. If you’re just beginning the transition to minimalist footwear, you’ll want to take some time to adjust to it or start with something with a bit more padding between your foot's sole and the ground. For working out and casual use, we recommend wearing these shoes for as long as you feel comfortable and then increasing that time frame as foot and musculoskeletal adaptations occur. If you’re hoping to make the Xero HFS your next go-to running shoe, we recommend wearing them for short distances at first and listening to your body as you go. It's easy to overdo it in the early stages, so we encourage you to exercise care and restraint and observe the signals your body is sending you. We also encourage you to view our article entitled How to Transition to Minimalist Shoes for more info on this important topic.
When used in combination with Correct Toes, a medical-grade silicone toe spacing device, the Xero HFS gives you the opportunity to naturally strengthen your foot (and realign your toes) with each and every step you take. Whether you’re running or working out in them, the HFS's flexibility and near-weightlessness allow your foot and ankle to respond to the ground, promoting the kind of brain-to-foot awareness that can maximize your performance, enable musculoskeletal health gains, and improve the quality of your footfalls. If you’re looking for a trail shoe to tackle gnarly terrain, you might consider other models (like the Xero TerraFlex, for example), but if you’re highly adjusted to minimalist shoes and need something for flat, packed trails, the HFS provides the platform and foot freedom-of-motion to take you there.
SHOP CORRECT TOESAs we’ve already mentioned, the size and shape of the toe box of the Xero HFS provide adequate room for most users to comfortably wear Correct Toes toe spacers while active. When we paired these shoes with Correct Toes and Injinji toe socks, we found it akin to wearing Correct Toes with sandals, as the breathability and comfort were truly unmatched. When using other helpful footgear in combination with a given shoe, it's essential that the shoe not impede or encroach upon the foot or toes in any way, and in this regard, the Xero HFS—a wide toe box running shoe—delivers.
Because the Xero HFS is, at its core, an athletic shoe, the use of Pedag metatarsal pads is recommended on a person-to-person basis. Because the transverse arch is usually activated while running, many runners find metatarsal pads unnecessary. That said, if you’re using the HFS for gym workouts or for casual strolls around town, or if you have a ball of foot condition you're looking to actively address, we've found that they accommodate metatarsal pads as well as any other shoe we’ve tested. Also, those looking to enhance balance, posture, agility, and general foot/body awareness might consider pairing the Xero HFS with Naboso insoles, swapping out the existing shoe liner for these thin, flexible, and textured inserts instead.
SHOP HELPFUL FOOTGEARThe short answer is yes! It is certainly possible to run a marathon in the Xero HFS shoe. The longer answer is: Running a marathon in the Xero HFS minimalist running shoe can be a positive and empowering experience, but it's important to consider your individual needs and preferences. This lightweight athletic shoe offers a barefoot feel with lots of sole flexibility, which makes it a great choice for runners who already have some familiarity with this kind of “barely-there” footwear. Prior to the gun going off on race day, it’s important to ensure that your feet are accustomed to this kind of barefoot running shoe and that you've trained in the HFS extensively. It's also advisable to consider the terrain and conditions of the marathon course itself, as ultraminimalist shoes may not be ideal for all types of surfaces. Ultimately, the suitability of the Xero HFS for running a marathon depends on your running style, your current level of foot strength and resiliency, and your comfort with minimalist footwear, so it's essential to make an informed decision based on your personal running—and foot health—journey.
Xero recommends ordering a half-size up in the HFS, as they tend to fit a bit small, whereas the sizing suggestion for the HFS II is to order your normal US shoe size. We followed these guidelines for testing, and the recommendations were spot on. Wide toe box shoes tend to feel a bit loose around the forefoot at first, so if this is your first foray into minimalist footwear, understand that this is a common experience and that it will come to feel normal over time. In fact, for most people who switch from tapering toe box athletic shoes to wide toe box versions, there is usually no going back.
Also, to know that you've achieved a great fit in the Xero HFS, you’ll want to assess where your toes rest within the shoe when standing. We often find that it's best to have about 1 centimeter of space between the ends of your toes and the front of the shoe's toe box. This usually leaves enough space to accommodate the toe lengthening and other beneficial foot adaptations that inevitably come with using this style of shoe for weight-bearing activities.
As with most of the Xero models we recommend, we advise that women order the men’s version of the HFS when making their purchase. Going for a more gender-specific fit, Xero opted to make the toe box of the women’s model relatively narrower than the men's version, but we feel that both men and women alike have the potential for a similar range of toe splay and that most women can benefit from the same relative toe box width as men.
Because Xero recommends going a half-size up in the HFS, women interested in this shoe can simply adjust the sizing down by one full size to determine their comparable size in the men's version. So, for example, if you normally wear a women's US size 8 shoe, consider ordering a 7 in the men's Xero HFS instead. For the HFS II, women will want to adjust the sizing down by 1.5 to determine their comparable size in the men's version. For example, if you normally wear a women's US size 8 shoe, consider ordering a 6.5 in the men's Xero HFS II instead.
Other than differences in the relative toe box width and the available colorways, all design elements of the men’s and women’s Xero HFS are identical.
SHOP XERO HFS SHOESAs with all ultraminimalist footwear, you should first consider where you are on the path to transitioning to barefoot-style shoes. With a 5 mm, highly flexible outsole and lightweight, airy upper, the Xero HFS is like a thin protective sheath for your bare feet. If you have sensitive feet or if you’re still adjusting to shoes with a completely flat sole, we’d recommend starting with a more transitional-type shoe (such as the Lems Primal Pursuit) or easing into use with care.
Additionally, because the Xero HFS sports a minimalist design to help optimize athletic performance and natural foot function, we can’t attest to their extreme long-term durability. Most athletic shoes of similar weight and construction are considered “race shoes,” and they might only survive a handful of races before being replaced. We can attest, however, that the Xero HFS is more durable than most race shoes, but this shoe may not last as long as bulkier, over-manufactured daily joggers. The trade-off, of course, primarily comes in the form of foot health benefits, as barefoot-style shoes such as the HFS provide the opportunity to restore optimal foot form and function through a natural fit and feel.
The Xero FHS II (pictured above, in Blue Aster), the successor to the original HFS, possesses the same DNA as its forebearer, but it incorporates a few key updates that improve upon the already stellar design of this vaunted Xero classic. In addition to the updated sizing recommendation mentioned earlier (i.e., order your regular US shoe size as opposed to a half-size up), the HFS II has a new tread design and pattern that provides some additional grip and makes it easier to take these shoes on off-road adventures. The Xero HFS II also includes a thin layer of Xero's BareFoam inside the shoe, which serves to provide a wee bit of extra protection for your foot's sole while helping to smooth out your ride. Other than these updates, as well as some new color options in the HFS II, these two iterations are pretty much identical.
When we first tried on the Xero HFS, we were absolutely amazed at how light and flexible these shoes are. Xero has truly maximized the minimalist feel with the use of their relatively thin FeelTrue rubber outsole and the breathable nature of the HFS's upper, and all other specs meet our demands for foot-healthy athletic shoes. This comfortable barefoot running shoe is flat from heel to toe, flexible in both the sole and upper, expansive in the toe box, and low in overall stack height. It also allows for excellent tactile feedback so that you can enjoy higher-quality footfalls and a more efficient and natural gait. Combined with the fact that these shoes are moisture-wicking, compatible with a variety of helpful footgear, and have a unique, tire tread-inspired tread pattern, the Xero HFS is most certainly in the pantheon of the best minimalist athletic shoes available on the market today.
The Xero HFS (and HFS II) scores 4.5 (out of 5) on the NFAR scale, which puts it in the “excellent” range for foot-healthiness.
The Xero HFS (and HFS II) shoe is Natural Footgear Certified, which means that it lives up to our strict criteria for what constitutes a healthy and beneficial natural foot product. In order to receive Natural Footgear Certification, products must conform to the key criteria we have identified as essential in supporting long-term foot and musculoskeletal health, and footwear must additionally score at least 4.4 out of 5.0 on the NFAR scale.
Disclosure:
We may receive affiliate compensation in connection with the purchase of footwear mentioned on this page (this doesn't cost you, the purchaser, anything, and it helps to keep Natural Footgear going). Even though we may receive compensation, we always give our honest opinions, findings, beliefs, or experiences on or about all models. See our Ethics Policy for more details.The Xero Kelso is a foot-health-positive minimalist shoe that seamlessly blends sporty style with formidable function. Known for their ultraminimalist approach... Read more
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