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Running Apparel • July 19, 2023

On Running Ultra Apparel Review: Mountain Race Ready

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What You Need To Know

Style to the max

Black, white, and mint green, what could be better?

Ready to fly

That might be Hoka’s thing, but this fabric basically disappears on the run

Get ya' cheese out

Swiss engineering don’t come cheap

EMILY: What would you say if I told you there was a secret lab on the other side of the Atlantic in the mysterious realm of Zurich, where a posse of genius wizards reside? And that these wizards are obsessed with cooking up a line of trail running gear capable of transforming you into the deftest of deer. I mean, would you say, “Dream on?” You’d be one hundred percent correct. The Swiss company On aims to create high-performance shoes and attire that enable you to reach that flow state on the trails as quickly and for as long as possible.

So they’re scientists and athletes and not wizards, but the result is the same — products crafted with planet-friendly technology that looks and feels like a dream. I’d never been introduced to On before, but from the first time I left the house in their Ultra-T, Ultra Shorts, and middie socks, I felt unhindered and like I could just plain fly. But, beyond the compliments I received from runners and non-runners alike, traversing the trails for the first time in this apparel marked the dawn of a new era for me, where I experienced that elusive mindset where movement and immersion in the moment were unified. Light-weight yet tangibly durable material, wicked smart pocket options, and moisture-wicking magic meant smiles for miles.

On Ultra Shorts

EMILY: I like to run fast when possible, juking and jumping over roots and rocks, bombing hills wildcat style, and pushing the envelope up climbs. The On Ultra shorts were designed for speed and distance and were inspired by elite trail runners who would instantly leave me in the dust. So after five miles in 88-degree weather on some technical trail, I was delighted by the ultralight fabric and flexibility of these mid-thigh length bottoms. Not once did I have to pick, shift or readjust, even as the sweat started to pour. Plus, the comfy integrated brief offers extra protection and comfort- much appreciated on those gritty descents.

Because I am a staunch believer that all apparel should come with at least one pocket, I was so excited that the On Ultra shorts have six pockets (including three hidden around the waistline) that I pointed them out to a total stranger standing in line at the grocery store — “Look at this! I can put my phone here, some TP, some snacks or salt over yonder, and my car keys in this pocket!” She seemed less impressed than I was, but that’s beside the point because, on long runs, I’ll use all of that storage.

In addition to storage, the Ultra shorts get bonus points for just plain looking sharp, which I attribute to the soft and stretchy waistband that sits just below the belly and boasts an integrated waistband complete with an inconspicuous chord stopper you can adjust with one hand if needed.

If the On Ultra shorts weren’t so pricey, I’d say they were flawless, but $119 for a single pair of shorts, elite-performance or not, feels extravagant. However, I’ve elected to rock these two times more often than any other pair I own, including top-ranking Patagonia and Outdoor Research trail shorts—anything for the flow, especially on race day.

PRICE: $119

Shop On Ultra Shorts - Women

On Ultra-T

EMILY: The On Ultra line of apparel is undeniably engineered for precisely that — the runner committed to going the distance, from marathons to 100 milers and beyond. And that means finetuning every detail of this feather-light performance tee, down to the undetectable seams and the breathable mesh back. No seams equal no chafing, which equals a less painful post-race shower experience and abundant joy.

I wore the extra small as I am admittedly rather scrawny above the waist, and the soft, stretchy Ultra-T delivered a tailored fit without awkward tightness or friction, unlike my prom dress from 25 years ago. I can confidently say that the Swiss engineers at On have nailed the unique blend of recycled material, so the paper-thin material mirrors your every move like a synchronized swimmer. I was so comfortable I honestly stopped paying attention to the shirt and got lost in the lull of the woods. What else can a girl ask for?

A pocket would be ideal… Enter the side stash pocket, a mini but mighty storage feature perfect for a few gels, a GPS tracker, or a treasure map. And because this shirt will be along for the long haul, lovingly placed reflective details have been added so you and the raccoons can be seen as the sun dips down for those extra-long races.

In the end, the only thing that chafes about the On Ultra-T is the $100 price tag — a little hefty compared to other performance tops.

PRICE: $99

Shop On Ultra-T - Women

On Performance Mid Sock

EMILY: Oddly enough, I’m reasonably well versed in the sock department, having sampled everything from toe socks to Balega, Smartwool, Wright, and Darn Tough. Not familiar with the array of socks out there? Our experts at Believe In the Run have compiled a mountain of reviews over the years. I quickly learned how critical it is to pull on the correct socks for the occasion, but who knew there were so many variables to consider — cushion, height, and material? When you spend hours beating up your trotters, especially if water and sweat are involved- which is always- socks can make or break the state of your feet and your focus.

On has designed a Performance Mid Sock that will quite literally prime your feet. I kid you not — the slightly raised motif at the arch effectively activates sensory receptors to prepare your feet for the adventure. It’s like giving your dogs a shot of espresso.

The Performance Mid-Sock is crafted from 90% recycled polyester from Slovenia, so your footprints are almost carbon-free. I was surprised at the buttery texture of this sock, which maintained its integrity even after a few trips through the wash — no one likes socks stiff enough to be used for origami. After three multi-hour runs in the heat, rain, and grit — I had zero blisters and hotspots. Typically, I stick with the below-the-ankle variety paired with compression sleeves on my calves for runs over three hours, but with the increasing prevalence of ankle collar uppers in trail shoes, the mid-length was perfect and protected my Achilles from any potential rubbing. Even when things got extra toasty, the climate in my shoes remained balanced, a subtle comfort made possible with enhanced breathability. For $22, On’s Performance Mid Sock is my go-to for race day from here on out.

PRICE: $22

Shop On Performance Mid Sock

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girl running in a red tanktop wearing a hat
Emily Hanson
Mid-Atlantic Trail Reviewer

Born and raised in Smaltimore (Baltimore), Emily relishes running for hours in the woods. It’s where she works out the kinks in her approach to being a mother, partner, writer, and a better human being.

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