Under Armour Undeniable 4.0

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Under Armour Undeniable 4.0

This Under Armour gym bag series is an established option for multi-sport athletes. So established that it’s the 4th iteration of the Undeniable series because of popular demand. This is a fairly feature-filled bag that costs a little more because of its popularity, but also because of its quality.


  • There are plenty of sizes and vivid colorways to choose from
  • The overall construction is sturdy
  • You can stay organized with all the pockets
  • There’s a built-in shoe compartment
  • Storm tech made it highly water-resistant


  • Shoulder strap not as good when carrying heavier loads


Gym bags have certain design features that appeal to different people. The Undeniable 4.0 is well suited for basketball, soccer and even racket sports. It’s a sports bag for everyday training too and, increasingly, a duffel bag option for weekend trips.

The construction can handle your training essentials without ripping, whether you’re into lifting, soccer, boxing, or any active lifestyle. Paired with UA’s Storm technology, the high water resistance will keep your items dry under showers.

After some rigorous testing, here’s what this duffel bag from Under ARmour has in store for you.

Train in Style

Under Armour has been one of the most famous go-to brands for those who love living an active lifestyle. Their Undeniable 4.0 sports bag makes it easier to carry your training essentials, and you also rock fitness sessions in style.

You can take a pick from numerous designs and sizes, and all of them seem to embody the durability to go head-on with your discipline. With easy access and organization, you stay clutter- and stress-free while counting your reps, sets, laps, or rounds.

It’s a sports bag for the modern-day fitness enthusiast. Undeniable 4.0 is a fairly-priced option that appears to perform and survive well.

Specs & Features

  • Materials: 100% Polyester, Textile Lining, UA Storm Technology
  • Sizes: 30 Liters, 41 Liters, 58 Liters, 85 Liters
  • Colors: Academy Blue/Silver, Black/Silver, Red/Silver, Baroque Green/Comet Green, Black/Metallic Gold, Mauve Pink/Ash Plum, Cordova, Starlight/Breeze, etc.

Construction and Design

Though it might seem like Undeniable 4.0 has nothing special in its design, this polyester-made sports bag carries Under Armour’s signature STORM technology (more on that in a bit). On the outside, it’s got a typical duffel bag look. But what do we like most about this US sports bag aesthetically? The colors are vivid, and they come in both plain and adventurous combos! You can also choose from four sizes- xs, small, medium, and large. (Note: the sizing runs bigger than expected.)
Now, let’s take a closer look at Undeniable 4.0’s build. Since it’s polyester-made, you can expect that it has good wrinkle and abrasion resistance. It also won’t stretch or get heavier when in contact with water since it doesn’t absorb moisture. Plus, this sports bag comes with US’s Storm technology-the fabric was DWR-treated to amp up its water resistance.

Water beads and rolls off as soon as it touches the fabric. However, it’s worth noting that it’s not waterproof. Your stuff will stay dry for a short time under light showers but not for long exposure under torrential rain. You might want to check out waterproof alternatives like Canway Sports Gym Bag, Thule Chasm Duffel, and King Kong Heavy Duty Duffel. Or, you might as well opt for a waterproof backpack.

The stitching seems durable. There are rare complaints about the seams coming off, but we haven’t had that issue. Undeniable 4.0’s zippers feel flimsy, so you might need extra caution when using them. The 2-way zipper at the main compartment also allows you to carry your sports bag from either shoulder.

Overall, this gym bag from Under Armour offers a decent build. Besides, you can choose from various designs and pick one that speaks out for your personality.

Harness System

Undeniable 4.0 has a standard adjustable shoulder strap webbing. It does what it’s supposed to, but not as comfy when you’re carrying it for long periods. There’s also a bit of confusion regarding the padding. The description of this sports bag didn’t clarify that the xs/small doesn’t include a pad and has a fixed strap. Only medium and large/xL have padding in the removable shoulder strap. It’s a bummer since the pad alleviates a bit of skin-digging irritation.


With lots of compartments on board, we’ve ended up using this bag on all sorts of things other than sports too. Undeniable 4.0 is ready to accommodate all your essentials, whether you’re off to the gym, for a quick trip, or training in the field.


Under Armour Undeniable 4.0 Sports Gym Bag is a good option that won’t rip holes in your pocket. It allows you to choose size and design according to your preference and intended purpose for roughly $35-$122.

Durability and water resistance are decent enough to withstand the test of time (under normal use). But still, manage your expectations. It’s not for super heavy hauling. This sports bag is meant for, well, training and gym sessions. You have duffel bags made for rugged and traveling purposes if that’s what you need.

The value Undeniable 4.0 returns for its price is reasonable. It’s not the best of the bunch- not the most comfortable or heavy-duty. But within its price point, this sports bag is an option that won’t let you down.

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