Our verdict

Implementing innovations is a risk. But Under Armour's unique SlipSpeed shoe happens to be a very successful experiment. With its convertible heel and BOA lacing system, the shoe switches from a gym shoe to a cosy slipper in a matter of seconds! We loved its versatility for walking, shopping, light treadmill runs, and a mix of other sporty and mundane activities. We can't recommend it as a high-performance training shoe but if you need a multi-tool with the most effortless on-and-off, it's hard to think of a better option than the SlipSpeed.

Pros

  • Highly versatile: from gym to casual wear
  • Collapsible heel: shoe to slipper
  • Secure and easy-to-adjust BOA lacing
  • Hard-wearing upper
  • Lighter than average
  • Wide and grounded platform
  • Comfortable in-shoe feel
  • Very flexible profile
  • Excellent grip on smooth floors
  • Cooling pads regulate in-shoe temperature
  • Machine washable

Cons

  • Not for intense training and lifting
  • Lacks lateral support
  • Exposed foam wears fast outdoors
  • Very little ventilation
  • Upper creases easily

Audience verdict

90
Superb!
  • Top 14% most popular training shoes

Who should buy

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

Under Armour SlipSpeed review

Who should NOT buy

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.

Under Armour SlipSpeed lab test

Breathability

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.

Under Armour SlipSpeed Breathability microscope

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

Under Armour SlipSpeed Breathability microscope test

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!

Under Armour SlipSpeed BOA Iso-Chill padding

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

Test results
SlipSpeed 2
Average 3.2
Compared to 32 skipping rope training shoes
Number of shoes
1
Breathability
5

Durability

Toebox durability

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!

Under Armour SlipSpeed Toebox durability comparison

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 SlipSpeed upper material

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. 

Test results
SlipSpeed 5
Average 2.7
Compared to 21 skipping rope training shoes
Number of shoes
1
Toebox durability
5

Heel padding durability

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!

Under Armour SlipSpeed Heel padding durability comparison
Test results
SlipSpeed 4
Average 2.5
Compared to 19 skipping rope training shoes
Number of shoes
1
Heel padding durability
5

Outsole hardness

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.

Under Armour SlipSpeed Outsole hardness
Test results
SlipSpeed 57.5 HC
Average 83.2 HC
We use an average of four tests. The photo shows one of those tests.
Compared to 32 skipping rope training shoes
Number of shoes
57.5 HC
Outsole hardness
94.5 HC

Outsole 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!

Test results
SlipSpeed 4.7 mm
Average 1.2 mm
Compared to 17 skipping rope training shoes
Number of shoes
0.0 mm
Outsole wear
2.0 mm

Outsole thickness

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.

Under Armour SlipSpeed Outsole thickness
Test results
SlipSpeed 0.0 mm
Average 3.7 mm
Compared to 32 skipping rope training shoes
Number of shoes
0.0 mm
Outsole thickness
5.1 mm

Weight

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!

Under Armour SlipSpeed Weight

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.

Test results
SlipSpeed 10.16 oz (288g)
Average 10.79 oz (306g)
Compared to 32 skipping rope training shoes
Number of shoes
6.38 oz (181g)
Weight
13.83 oz (392g)

Cushioning

Heel stack

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).

Under Armour SlipSpeed Heel stack

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.

Test results
SlipSpeed 21.1 mm
Average 24.3 mm
Compared to 32 skipping rope training shoes
Number of shoes
13.7 mm
Heel stack
36.2 mm

Forefoot stack

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.

Under Armour SlipSpeed Forefoot stack

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.

Under Armour SlipSpeed profile

Test results
SlipSpeed 19.2 mm
Average 18.4 mm
Compared to 32 skipping rope training shoes
Number of shoes
10.6 mm
Forefoot stack
27.7 mm

Drop

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).

Under Armour SlipSpeed Drop
Test results
SlipSpeed 1.9 mm
Average 5.9 mm
Compared to 32 skipping rope training shoes
Number of shoes
1.8 mm
Drop
13.4 mm

Midsole softness

Note: a low durometer measurement equals a soft material, whereas a high measurement means it's firm.

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.

Under Armour SlipSpeed Midsole softness

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!

Test results
SlipSpeed 28.5 HA
Average 27.4 HA
We use an average of four tests. The photo shows one of those tests.
Compared to 32 skipping rope training shoes
Number of shoes
17.4 HA
Midsole softness (soft to firm)
47.0 HA

Insole thickness

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.

Under Armour SlipSpeed Insole thickness
Test results
SlipSpeed 4.8 mm
Average 3.8 mm
Compared to 32 skipping rope training shoes
Number of shoes
0.0 mm
Insole thickness
5.7 mm

Stability

Lateral stability test

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.

Torsional rigidity

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.

Test results
SlipSpeed 1
Average 2.7
Compared to 32 skipping rope training shoes
Number of shoes
1
Torsional rigidity
5

Heel counter stiffness

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.

Test results
SlipSpeed 1
Average 2.8
Compared to 32 skipping rope training shoes
Number of shoes
1
Heel counter stiffness
5

Midsole width in the forefoot

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!

Under Armour SlipSpeed Midsole width in the forefoot
Test results
SlipSpeed 117.3 mm
Average 109.6 mm
Compared to 32 skipping rope training shoes
Number of shoes
101.0 mm
Midsole width in the forefoot
117.3 mm

Midsole width in the heel

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).

Under Armour SlipSpeed Midsole width in the heel

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

Test results
SlipSpeed 93.9 mm
Average 86.8 mm
Compared to 32 skipping rope training shoes
Number of shoes
76.5 mm
Midsole width in the heel
97.4 mm

Flexibility

Stiffness

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. 

Test results
SlipSpeed 14.5N
Average 18.6N
We use an average of four tests. The video shows one of those tests.
Compared to 31 skipping rope training shoes
Number of shoes
6.8N
Stiffness
37.9N

Grip / Traction

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.

Under Armour SlipSpeed Lug depth

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

Size and fit

Internal length

Measuring the SlipSpeed's internal length in our regular men's US size 9, we got 269.8 mm. It is consistent with most other training shoes like the Nike Metcon 9, the Reebok Nano X4, and the Adidas Dropset 2.

On foot, we also felt that the shoe runs true to size lengthwise.

Under Armour SlipSpeed Internal length
Test results
SlipSpeed 269.8 mm

Toebox width at the widest part

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.

Under Armour SlipSpeed Toebox width at the widest part

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.

Test results
SlipSpeed 106.6 mm
Average 100.1 mm
Compared to 32 skipping rope training shoes
Number of shoes
90.4 mm
Toebox width at the widest part
108.0 mm

Toebox width at the big toe

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

Under Armour SlipSpeed fit

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

Under Armour SlipSpeed Toebox width at the big toe
Test results
SlipSpeed 80.7 mm
Average 78.2 mm
Compared to 25 skipping rope training shoes
Number of shoes
65.0 mm
Toebox width at the big toe
87.5 mm

Tongue: gusset type

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

Under Armour SlipSpeed Tongue: gusset type
Test results
SlipSpeed Bootie

BOA lacing

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.

Comfort

Slip-on

With convenience as its cornerstone, the SlipSpeed features a foldable heel collar that quickly turns the shoe into a slipper. You don't even need hands to push the collar down!

Switching gears from training to rest couldn't be any easier!

Under Armour SlipSpeed Training Shoes Slip on design

We found that there is a small pillow on the inner side of the foldable part. It works as the Achilles pad when the collar is up but turns into a heel crash pad when you fold the collar.

Under Armour SlipSpeed collar padding

But here is the caveat: if you have sensitive feet and prefer the bottoms of your shoes to be as smooth as the baby's bottom, you might be annoyed with the folded material beneath the heel.

Tongue padding

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.

Under Armour SlipSpeed Tongue padding
Test results
SlipSpeed 4.4 mm
Average 5.6 mm
Compared to 32 skipping rope training shoes
Number of shoes
1.0 mm
Tongue padding
10.4 mm

Removable insole

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

Under Armour SlipSpeed Removable insole
Test results
SlipSpeed Yes

Machine washable

To make the SlipSpeed even more enticing, Under Armour promotes it as machine washable. It is promised to last up to 200 wash cycles before starting to lose integrity.

Just follow these simple rules:

  • Place the shoes in a laundry bag (it may or may not come with the shoe depending on the retailer you buy it from)
  • Machine wash on cold delicate
  • Allow shoes to air-dry (tumble drying is not recommended as it can heat up the glue and the foam)

Under Armour SlipSpeed shoe pieces

Misc

Reflective elements

There are no reflective elements on the UA SlipSpeed.

Under Armour SlipSpeed Reflective elements
Test results
SlipSpeed No