Our verdict

Under Armour’s Charged Assert 9 might not be the speediest in the UA lineup, but in our opinion, it shines as a sturdy, stable ride with a firm yet flexible midsole. While it might not be our go-to for long distance or speed training, we strongly believe it could be your reliable gym or cross-training companion. And we're impressed by the outsole longevity, truly standing the test of time.

Pros

  • Remarkably comfortable and flexible
  • Outsole showcases ultra-durability
  • Enough cushion for heel strikers
  • Stable
  • Functions well as both a running and walking shoe
  • Amazing value
  • A great pick for Under Armour enthusiasts

Cons

  • Falls short in breathability
  • Heel lockdown leaves room for improvement
  • Midsole could use more bounce and feels somewhat firm

Audience verdict

84
Good!
  • Top 26% most popular running shoes

Who should buy

For beginners seeking a durable, wallet-friendly shoe that can multitask as a cross-trainer or walking shoe, we think the Charged Assert 9 is a superb pick. Even seasoned runners can rely on it, as we found, for easy or moderate runs. But it's only suited for those among us who appreciate a balanced or firm midsole.

Under Armour Charged Assert 9

Who should NOT buy

Here are some situations where we think that runners seeking a budget-friendly shoe might want to look elsewhere:

  • Fans of plush midsoles may find this one a bit too firm. In that case, we'd recommend the Nike Air Winflo 9.
  • Midfoot or forefoot strikers might not find enough stack height in this Under Armour shoe. A solid alternative for them that's still easy on your wallet is the Saucony Axon 2.
  • For those of living in colder climates, this shoe may not offer a pleasant running experience. The ASICS Gel Excite 9 performs far better in winter conditions.

Under Armour Charged Assert 9 parts

Breathability

At a quick glance, the breathability of the UA Charged Assert 9 doesn't appear to be impressive. However, we can't just rely on first impressions—we put running shoes through rigorous lab tests, that's what we do.

Our first step involves pumping smoke through the shoe to assess its breathability. Unfortunately, this particular Under Armour model is a bit of a disappointment in this area, earning a lower-than-average score of 3 out of 5.

While we can see a small amount of light coming through from the other side, it's minimal at best. This observation only confirms our initial impression of the shoe's subpar breathability. 

Under Armour Charged Assert 9 microscope

But nothing like the microscope for a deeper understanding of the upper. Under Armour has designed the shoe with a multi-layered engineered mesh that restricts airflow, and they have not included any ventilation holes in the design.

Under Armour Charged Assert 9 microscope 2

Test results
Charged Assert 9 3
Average 3.9
Compared to 185 running shoes
Number of shoes
1
Breathability
5

Durability

Toebox durability

While sometimes poor breathability in shoes can be attributed to a rugged upper, sadly, that's not an excuse for the Charged Assert 9.

We conducted our Dremel test and the results left us no choice but to give it a disappointing 1 out of 5. Indeed, the shoe sports a reinforced toe cap, which provides good protection against abrasion. However, the rest of the upper isn't up to par, making the shoe extremely susceptible to wear and tear.

Under Armour Charged Assert 9 Toebox durability
Test results
Charged Assert 9 1
Average 2.1
Compared to 119 running shoes
Number of shoes
1
Toebox durability
5

Heel padding durability

Our disappointment didn't end there. When we applied the Dremel to the heel area, debris began flying in all directions.

This unpleasant surprise forced us to hand out another underwhelming score of 1 out of 5.

Under Armour Charged Assert 9 Heel padding durability
Test results
Charged Assert 9 1
Average 2.9
Compared to 115 running shoes
Number of shoes
1
Heel padding durability
5

Outsole hardness

But the tide turned when we assessed the outsole.

We gauged the rubber hardness at 86.0 HC, a truly high value, suggesting that this shoe should offer exceptional durability.

Under Armour Charged Assert 9 Outsole hardness
Test results
Charged Assert 9 86.0 HC
Average 80.3 HC
We use an average of four tests. The photo shows one of those tests.
Compared to 237 running shoes
Number of shoes
55.5 HC
Outsole hardness
92.8 HC

Outsole durability

Indeed, upon utilizing the Dremel one more time in this shoe, we confirmed that the rubber Under Armour uses is incredibly robust.

Outsole thickness

With a remarkable thickness of 4.9 mm, this outsole stands as one of the thickest we've ever gauged in a road running shoe.

Couple this with the outstanding durability we've witnessed in the previous tests in our lab, and we confidently predict that we'll wear ourselves out long before we even come close to wearing down this impressive outsole.

Under Armour Charged Assert 9 Outsole thickness
Test results
Charged Assert 9 4.9 mm
Average 3.2 mm
Compared to 257 running shoes
Number of shoes
0.0 mm
Outsole thickness
6.6 mm

Weight

Let's be clear—this shoe isn't marketed or designed to be a lightweight daily trainer. And tipping the scales at 10.2 oz or 290g, it goes past the 10 oz mark by just a smidge.

It's important for us to remember that we're dealing with a budget-friendly shoe here, tailored for easy or moderate runs. In this context, lightness isn't the top priority, and this weight it's acceptable.

Test results
Charged Assert 9 10.23 oz (290g)
Average 9.38 oz (266g)
Compared to 257 running shoes
Number of shoes
5.26 oz (149g)
Weight
12.56 oz (356g)

Cushioning

Heel stack

It's well known that beginners frequently prefer affordable shoes and they often strike the ground with their heel. Thats the reason why we're noticing a clear trend among entry-level shoes from many brands.

They're leaning toward generous stack heights in the heel. In the CA9, our precise measurement came at 34.0-mm stack in the heel.

Under Armour Charged Assert 9 Heel stack
Test results
Charged Assert 9 34.0 mm
Average 33.5 mm
Compared to 256 running shoes
Number of shoes
7.6 mm
Heel stack
42.7 mm

Forefoot stack

However, for those of us who are forefoot or midfoot strikers, the forefoot section comes up a bit short on foam.

Measuring at 23.1 mm, once we deduct the outsole and the insole, there's barely any foam left, as the picture clearly illustrates.

Under Armour Charged Assert 9 Forefoot stack
Test results
Charged Assert 9 23.1 mm
Average 24.7 mm
Compared to 256 running shoes
Number of shoes
7.6 mm
Forefoot stack
34.8 mm

Drop

A tall heel coupled with a low forefoot inevitably results in a significant heel-to-toe drop.

For the Charged Assert 9, we measured a considerable drop of 10.9 mm. Again, this one is clearly tailored with heel strikers in mind.

Under Armour Charged Assert 9 Drop
Test results
Charged Assert 9 10.9 mm
Average 8.8 mm
Compared to 256 running shoes
Number of shoes
-0.8 mm
Drop
16.1 mm

Insole thickness

Measured with our caliper at 4.4 mm, the insole is not setting off any fireworks, but it's not giving us any headaches either! 

Under Armour Charged Assert 9 Insole thickness
Test results
Charged Assert 9 4.4 mm
Average 4.4 mm
Compared to 252 running shoes
Number of shoes
1.5 mm
Insole thickness
9.8 mm

Midsole softness

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

If you're a fan of ultra-soft midsoles, stay away from this one.

However, it's not as tough as a brick underfoot—we confirmed that with a hardness rating of 27.8 HA, but it doesn't offer the dreamy, plush comfort you'd find in shoes like the ASICS Novablast 3.

Under Armour Charged Assert 9 Midsole softness
Test results
Charged Assert 9 27.8 HA
Average 23.5 HA
We use an average of four tests. The photo shows one of those tests.
Compared to 238 running shoes
Number of shoes
6.5 HA
Midsole softness (soft to firm)
52.5 HA

Midsole softness in cold

Note: a low durometer measurement equals a soft material, whereas a high measurement means it's firm.
Under Armour Charged Assert 9 Midsole softness in cold

Difference in midsole softness in cold

After we let the CA9 chill out in our freezer for 20 minutes, the foam got much firmer.

Our durometer clocked in at 34.5 HA, which isn't what we wanted to obtain, unfortunately.

We witnessed a 24.3% change here, which lines up with what you'd expect from the average shoe. For a midsole made of EVA, that's not a disappointing outcome after all.

Under Armour Charged Assert 9 Midsole softness in cold
Test results
Charged Assert 9 24.3%
Average 26.4%
Compared to 237 running shoes
Number of shoes
0%
Difference in midsole softness in cold
125%

Stability

Lateral stability test

As a moderately firm running shoe, you'd expect the Charged Assert 9 to be stable. But is it?

The truth is, right off the bat, we could tell stability wasn't going to be a problem for this Under Armour running shoe.

Torsional rigidity

This shoe outshines most regarding flexibility, enhancing comfort and effortlessly transforming from a running shoe into a casual, everyday walking shoe.

This added versatility is certainly a delightful bonus for those who want a do-it-all shoe. We rated it at 2/5 in our torsional rigidity test.

Test results
Charged Assert 9 2
Average 3.2
Compared to 234 running shoes
Number of shoes
1
Torsional rigidity
5

Heel counter stiffness

Being a shoe marketed for beginners and at a entry-level price, it made no sense to put a firm heel counter on it. That's why we inmediately noticed that it was really pliable, and we gave it another 2/5.

We did notice a bit of heel slippage when picking up the pace. Fortunately, a quick switch to a runner's knot put an immediate stop to that issue.

Test results
Charged Assert 9 2
Average 2.7
Compared to 218 running shoes
Number of shoes
1
Heel counter stiffness
5

Midsole width in the forefoot

With a substantial width of 111.3 mm in the forefoot, the Charged Assert 9 feels stable once more. Plus, it handles corners reliably, making us feel secure no matter the turn.

Under Armour Charged Assert 9 Midsole width in the forefoot
Test results
Charged Assert 9 111.3 mm
Average 113.4 mm
Compared to 257 running shoes
Number of shoes
100.5 mm
Midsole width in the forefoot
126.5 mm

Midsole width in the heel

The heel is where this shoe really needs to be wide, considering it's designed with heel strikers in mind, as we said before.

We're pleased to say that, measuring in at 90.5 mm in our lab, it's indeed broad enough to ensure all heel landings are safe and secure.

Under Armour Charged Assert 9 Midsole width in the heel
Test results
Charged Assert 9 90.5 mm
Average 90.2 mm
Compared to 257 running shoes
Number of shoes
74.9 mm
Midsole width in the heel
106.6 mm

Flexibility

Stiffness

There have been times when we thought a shoe was incredibly flexible, only for the numbers to prove us wrong. But this isn't one of those instances.

It took us a mere 17.7N of force to bend this shoe to 90 degrees, and with this measurement, the Charged Assert 9 easily secures a spot in the top 10% for flexibility.

Test results
Charged Assert 9 17.7N
Average 29.2N
We use an average of four tests. The video shows one of those tests.
Compared to 240 running shoes
Number of shoes
2.2N
Stiffness
94.4N

Difference in stiffness in cold

But does it remain flexible in cold conditions? Well, not quite as much as we might like.

Even though it's more bendable than most shoes, the feel definitely changes somewhat in the cold. That's the thing with EVA midsoles.

You might have picked up on the massive disparity between our first and second measurements. Indeed, with a whopping 82.6% difference, the shoe's performance is downright disappointing.

This enormous difference ensures the shoe will feel drastically different when you're running in cold weather.

Test results
Charged Assert 9 82.6%
Average 39.1%
Compared to 240 running shoes
Number of shoes
0%
Difference in stiffness in cold
148%

Size and fit

Length

For us, the CA9 felt just a tad too small. If you're often caught between sizes, consider going up half a size. However, most runners should stick with their usual size.

Under Armour Charged Assert 9 Length
Test results
Charged Assert 9 Runs small

Toebox width at the widest part

In crafting a versatile, multi-purpose shoe, it's critical that manufacturers avoid creating narrow uppers—they can really hinder comfort during casual wear or walking.

Happily, this Under Armour stands out with its wide design, measuring an impressive 99.4 mm at the upper's broadest point, exceeding the width of most average shoes.

Under Armour Charged Assert 9 Toebox width at the widest part
Test results
Charged Assert 9 99.4 mm
Average 98.1 mm
Compared to 258 running shoes
Number of shoes
89.5 mm
Toebox width at the widest part
109.1 mm

Toebox width at the big toe

On the downside, the shoe runs a bit narrow in the big toe area. This could be a slight discomfort for runners whose feet are particularly wide at the toes.

Our measurement came in at 74.7 mm in this area.

Under Armour Charged Assert 9 Toebox width at the big toe
Test results
Charged Assert 9 74.7 mm
Average 77.8 mm
Compared to 130 running shoes
Number of shoes
67.6 mm
Toebox width at the big toe
90.4 mm

Tongue: gusset type

Typically, affordable running shoes tend to skip on some features like a gusseted tongue. Unsurprisingly, this shoe also follows the same trend.

Under Armour Charged Assert 9 Tongue: gusset type
Test results
Charged Assert 9 None

Comfort

Tongue padding

Kudos to UA for this tongue! With a cushy 7.1 mm of padding inside, you can lace up as tight as you want.

Under Armour Charged Assert 9 Tongue padding
Test results
Charged Assert 9 7.1 mm
Average 5.7 mm
Compared to 254 running shoes
Number of shoes
0.5 mm
Tongue padding
14.2 mm

Heel tab

As we said just before, budget-friendly running shoes often miss out on additional features such as a gusseted tongue.

However, Under Armour pleasantly surprised us by including a heel tab in this one! We are truly appreciative of this cool touch as it makes slipping our feet into the shoe a breeze.

Under Armour Charged Assert 9 Heel tab
Test results
Charged Assert 9 Finger loop

Removable insole

We've found no trouble replacing the insoles with those from other shoes, since the included ones are not glued down at all.

Under Armour Charged Assert 9 Removable insole
Test results
Charged Assert 9 Yes