Don’t call the Infinite Mega—with it’s ankle cutout and odd lacing system—a gimmick. As with most things, you should never judge a book by its cover. Even when it’s cover has two Boa dials.
| Type | Road |
|---|---|
| Weight | 10.5 oz (M), 8.9 oz (W) |
| Drop | 8 mm |
| Heel Height | 43 mm |
| Forefoot Height | 35 mm |
- Why Run in This Shoe: The Infinite Mega is an long-distance road shoe with a bouncy ride and customizable dual-dial lacing system
- Fastest Marathon Runners: Why Run in This Shoe, New Balance SuperComp Trainer v2
- Midsole Foam: Why Run in This Shoe
- Key Tech: Hovr+, supercritical foam
How the Under Armour Infinite Mega Fits
Under Armour collaborated with Speedland to create a long-distance road running shoe with an adaptable fit. Speedland, which is helmed by design duo Dave Dombrow and Kevin Fallon (both previously worked at Under Armour), has used Carbitex carbon-fiber plates, Boa dials, and Michelin rubber to up the ante on shoe design. Every nuance of the Infinite Mega is intended to support the ultimate long run.
Its aesthetic may look Tatooine trader—we tested the muted beige “white quartz/desert sand” edition—but its unconventional style is with purpose. The suede bands that wrap over the instep, for instance, help secure the midfoot with a turn of a Boa dial. The ankle cutout obviously allows airflow but also prevents excess movement; no need to use heel lock lacing here (not that that’s a possibility without eyelets or laces). The Boa dial tightens the collar to your preferred level of comfort without having to worry about bunching up the heel collar. Because the shoe is available in unisex-only, the Boa placement is ideal for women runners, who tend to have a narrower heel and wider midfoot.
As a wide-footed runner, I appreciated the accommodating fit around the toe area and midfoot, as well as how secure the suede straps were once I twisted the Boa dial. It was satisfying watching the little strings tuck and tighten as I turned. Many testers felt the same way.
“It fit 100 percent in all the places it should,” said Erica Fisher, wears a women’s 10. “It was such a nice comfort over the top of my foot when ‘all laced’ up.”
“The Boa lacing system allows you to lock into a specific desired stability and fit, and have that hold without adjustment throughout the run,” said tester David Fisher. “Never having to re-tie and never feeling any unwanted movement within the shoe was incredible.”
Though David was a fan of the dial system, he said the ankle cutout “seemed like a design flaw” that caused his heel to get wet when he hit small puddles.
You might also fear that the opening would allow gravel to sneak inside the shoe, but we found this wasn’t an issue. The only drawback with the Infinite Mega for me was pressure above my right ankle by the cutout. My experience seems to be isolated as no other tester complained about this area.
For testers who weren’t happy with the Boa lacing system, their chief reason was because of the shoe’s wideness and rigidity and the inability and to properly tighten.
“No matter how much I adjusted, I couldn’t get a secure fit,” said Sarah Pezzino, who has a flat foot and runs with a forefoot strike. “It felt loose and sloppy, almost like my foot was going to slide out with every step. The wide fit combined with poor lockdown made it feel completely unstable. Turning corners felt risky and, at faster paces, I had zero confidence in my footing.”
How the Under Armour Infinite Mega Feels
The shoe is clearly in “super trainer” territory—43mm in the heel and 35mm in the forefoot—and has a supercritical foam footbed and a “mega” midsole carrier of Hovr+ foam.
“The firm cushion was great,” said Erica Fisher. “Form fitting perfection.”
David Fisher also liked the cushioning but found it overwhelming in the heel (Fisher is a midfoot striker). “The extra thick cushioning in the heel was a bit too much and made it feel a bit bouncy,” he said. “I prefer a less chunky cushion overall, but these were great for moderate speed, longer distance training.”
RW senior features editor Pavlína Černá, on the other hand, felt the foam didn’t have enough give to support her foot.
“It’s not the kind of cushioning you sink into,” she said. “It still felt supportive, yet not too stiff. But that impression only lasted for about 15 minutes. Then the shoe felt too rigid and the cushioning kinda didn’t matter.”
How the Under Armour Infinite Mega Rides
Like Černá, Pezzino also wished the foam molded to her foot as she ran. She compared the Infinite Mega to other shoes that provided that sink-in feel.
“The soft, unstructured feel made me feel slow and unsteady when picking up the pace,” said Pezzino, whose average training pace is 7:30. “If you want a shoe that helps with energy return and propulsion, this is not it. The softness actually worked against me, making me feel sluggish and unstable.” She used Brooks Hyperion Max, Saucony Endorphin Speed, and Nike Pegasus as comparisons, finding all of the above offered a more versatile, responsive ride.
Pezzino and Černá were the minority in our pool of testers, however. Mitchell Ricker, for example, not only found the Infinite Mega runnable but also found it extremely versatile.
“The cushion is my favorite part of this shoe,” said Ricker, who previously tested the Altra Mont Blanc Carbon and Hoka Arahi 7. “Long runs, short speedwork uphill and down; the shoe performs as well or better than any other I’ve ever worn.”
Narrow-footed runners may find the Infinite Mega too wide, no matter how much they twist the Boa dial. There can also be a break-in period for some, due to the shoe’s stiff frame. But runners will find themselves surprised by the shoe’s springy ride and comfy fit. We’ve yet to put in ultra mileage, but the Infinite Mega proves there’s thoughtfulness behind its wonky exterior.
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Amanda Furrer, Runner’s World test editor, studied journalism at NYU and writing at Emerson College. She has reviewed gear and covered other topics in the running space for almost 10 years. Since 2013, she has consecutively run the Boston Marathon. She also has a master’s degree in gastronomy from Boston University and was formerly a professional baker for two years before hanging up her apron.
