Under Armour SlipSpeed review

We believe that the UA SlipSpeed is a gem for people in search of:

• an all-in-one shoe: a home slipper, a gym trainer, a casual sneaker, a practical travel shoe, etc.
• a convertible heel that turns the shoe into a slip-on in a second
• a BOA lacing that is very quick and easy to adjust

If having a collapsible (drop-in) heel is not a must and you need a full-on training shoe for intense workouts, it is better to skip the SlipSpeed.

When your training regimen calls for the most stable and supportive footwear, we highly recommend the UA TriBase Reign 5.

And if you don't mind other brands, the Nike Metcon 9 and the Reebok Nano X4 are both top-rated trainers.

The UA SlipSpeed is a very grounded and minimally cushioned trainer. And it does feel that way on foot.

Measuring its heel stack with a caliper, we got a lower-than-average reading of 21.1 mm. Very similar to the Nike Metcon 9 (21.5 mm).

You can expect a sufficient amount of impact protection for walking and jumping sessions but it's not the same as the ultra-plush and cushy running shoes of today.

The forefoot portion of the SlipSpeed also offers more ground feel than cushioning. With a caliper measurement of 19.2 mm, it is just the same as the average cross-trainer.

We found that it hits a sweet spot between shock absorption and ground feedback. Both rope jumps and lifting felt at home in this trainer.

We thoroughly enjoyed a sense of underfoot control in the UA SlipSpeed.

There is practically no heel elevation in the shoe due to the very minimal heel-to-toe drop (1.9 mm). It means that the heel is almost at the same level as the toes (as if you were standing barefoot on the floor).

It helped us feel more planted and activated the Achilles tendon more than usual. So, if you struggle with ankle mobility, particularly during deep squats, we advise going with a higher-drop shoe (at least 6 mm).

If you are familiar with Under Armour's basketball shoes or running footwear, you will be pleased to see the brand's Flow cushioning foam in the SlipSpeed.

But don't expect the same softness in this trainer. Pressing our durometer against the shoe's Flow midsole returned 28.5 HA which is slightly firmer than average.

But on the bright side, we encountered a similar level of elasticity and energy return as in the other UA shoes we tested. There was a welcome touch of bounce for high-impact exercises like box jumps and burpees.

We even found it comfortable enough for short warm-up runs on the treadmill!

A generously padded insole makes the shoe even more comfortable for short runs, plyometrics, and long hours on the feet.

Based on our caliper measurement, it is thicker than average at 4.8 mm.

The SlipSpeed has a very accommodating toebox fit, judging by our medium-width feet.

Our caliper measurement showed 106.6 mm in the widest part of the trainer's forefoot which is a few millimeters wider than average.

But take that with a grain of salt because the shoe's upper material is pretty thick and the fit is easily tightened up by the BOA lacing. On foot, this UA shoe is more form-fitting than it seems.

There is also no give to the upper material whatsoever. Don't expect it to stretch out much after a break-in period.

The shoe's toebox has a rounded shape and no aggressive tapering. It never squeezed our toes offering pretty relaxed but secure confines.

Measuring the shoe's width at the big toe, our caliper showed 80.7 mm, a couple of millimeters wider than average.

Working together with the bootie, the BOA closure provides a highly secure lockdown in the midfoot.

This toggle lacing system takes seconds to adjust and can be regulated with just one hand, on-the-go. The knob turns in 1-mm increments allowing us to fine-tune the fit. To release the hold, all we needed to do was to pull the knob up.

If you feel uncertain about the ultra-thin cables, there is no reason to be concerned. These strings are made of the strongest man-made fiber in the world which is also used for laying cable at the bottom of the ocean. And it has long proven itself on snowboarding boots to.

Generally, the SlipSpeed offers a solid footing with its low-to-the-ground, firm, and wide sole. But the shoe fails miserably when it comes to lateral support and containment.

Having no supportive elements, the SlipSpeed fails to prevent the foot from spilling over the sole.

Where most cross-trainers feature solid TPU reinforcements, the SlipSpeed doesn't have any supportive elements.

Look how much the Reebok Nano X4 fights our ankle back to keep it in place.

If your workouts involve a lot of heavy lifting and forceful lateral movements, or if you deal with overpronation (excessive inward rolling of the foot), you must get a more supportive trainer. We recommend looking towards the Reebok Nano X4 and the Nike Metcon 9.

You can clearly see how little structure there is to the UA SlipSpeed as we twist it effortlessly with our hands.

On a scale from 1 to 5, where 5 is the stiffest, we rated this trainer with the lowest score of 1. It is much more pliable than the average training shoe.

It is pretty obvious that the shoe's convertible heel offers pretty much no heel hold.

It is a completely different design from a typical cross-trainer. You have to choose between having a firm heel hold and the option to swap between a slip-on and a shoe.

Example of a 4/5 heel counter stiffness.

Once again, we advise going for a full-on supportive shoe if you have fallen arches or moderate/severe overpronation.

Looks like the SlipSpeed mostly relies on its wide base for stability.

Notably wider than average, the shoe's platform creates extended contact points with the floor to give a better sense of control.

Measuring the widest part of the sole in the forefoot, our caliper showed 117.3 mm which is over 7 mm wider than average!

The SlipSpeed also turned out to be wider than average in the heel.

With a caliper reading of 93.9 mm, it is almost as wide as the Nike Metcon 9 (95.0 mm).

Having such a wide and flat base helped us feel surefooted when lifting and performing single-leg movements.

You can rest assured that the UA SlipSpeed bends enough to let you perform lunges, hold a plank, and walk around comfortably.

According to our force gauge, it only takes 14.5N of force to bend this shoe to a 90-degree angle. It is 30% less than it takes an average training shoe.

On the flip side, a more flexible profile makes it trickier to lift heavy as we found it harder to ground toes on the floor. 

The absence of a rubber outsole really helps the SlipSpeed to minimize the bulk.

Weighing it in a men's US size 9, we got a below-average measurement of 10.2 oz (288g). Nice and light!

On foot, this Under Armour shoe feels like an actual slipper! It got us through the gym session and then the rest of the day without a hint of foot-dragging.

With its neoprene-ish inner bootie and thick synthetic outer shell, the SlipSpeed doesn't let much air in or out.

As you can see in our breathability test above, the shoe's upper barely allows the smoke to escape the interiors.

And even when we tried hovering its half-cut upper over the light, no secret ventilation holes showed up.

Sure, the shoe's upper is full of perforations. But the reinforced padding beneath it simply doesn't let them work full time.

So, let's get this straight - the SlipSpeed is NOT a breathable trainer. If we compare it to other training shoes on a 1-5 breathability scale, this UA shoe deserves no more than a 2. But then how did it manage to keep our feet cool?

The answer is Iso-Chill padding throughout the inner lining and on the tongue. These cooling pillows did a great job of regulating the temperature inside the SlipSpeed and prevented our feet from heating up in the first place!

This is the first time we ever see something like this on a shoe, albeit a training shoe!

A mere glance at the shoe's sturdy upper promises durability.

After exposing the shoe's toebox material to our Dremel for 12 seconds, we saw a ridiculously minor scuff where most shoes develop a large hole!

Rating its toebox durability on a 1-5 scale, we confidently gave it the highest score of 5!

This reinforced material can handle a lot more wear and tear than a typical training shoe. Slashing it against the floor or gym equipment won't be an issue at all.

The only potential problem with the SlipSpeed's upper is that it tends to crease and chip off more than other uppers. It doesn't affect the shoe's integrity or durability but takes some points away from the looks.

Under Armour is quick to call these shortcomings "battle scars" because they only appear if the wearer has been training "hard enough." That's one very market-y way to put it. 

Because the convertible heel collar is the shoe's main highlight, we had high expectations for this part of the SlipSpeed. Especially when it comes to wear resistance.

Luckily, the brand chose a rather durable textile for the inner lining of the heel counter. Given how much back-and-forth folding and sliding it is meant to withstand, we are happy with its performance in our durability test.

Coming in contact with our Dremel for 4 seconds, the fabric showed very small signs of wear. This earned the shoe's heel lining a solid durability score - 4 out of 5!

The absence of a rubber outsole left us puzzled, to be honest. If the SlipSpeed is meant as a versatile knock-around, then why did Under Armour leave its foam exposed to wear and tear?

And it's not a firm type of foam either. Pressing our durometer against it showed 57.5 HC which is a whopping 45% softer than the average of training shoes! That's not very good news for the shoe's long-term durability.

Looks like concrete, asphalt, and other abrasive surfaces are not good friends with this UA trainer.

Meeting the sandpaper tip of our Dremel for 22 seconds, the shoe's foam was eaten alive. The tool burnt a hole as deep as 4.7 mm! That's over 3 mm deeper than average!

Unfortunately, we cannot recommend the Under Armour SlipSpeed for prolonged outdoor use, especially on highly abrasive surfaces.

But if your most common areas of habitat are home, car, coffee shop, and gym, then this shoe will serve you well.

Granted, the SlipSpeed's exposed foam undercuts many rubber outsoles when it comes to grip.

Softer and toothier, the Flow foam bites onto smooth gym floors like there is no tomorrow.

With its lugs facing all fronts, we found it easy to stop on a dime and change directions on the fly.

There are no reflective elements on the UA SlipSpeed.

The "tongue" (or the instep padding) of the SlipSpeed is not very thick. Showing only 4.4 mm on our caliper, it is a bit thinner than average.

But we found it to be just right to buffer the pressure from the BOA cables.

As a mule, the Under Armour SlipSpeed features a one-piece bootie upper that wraps around the foot with no gaps in between.

Because the shoe's insole is removable you can play around by replacing it with a custom orthotic to elevate the in-shoe comfort.