UltrAspire Alpha 6.0 Race Vest

The UltrAspire Alpha 6.0 Race Vest. All photos: iRunFar/Kristin Zosel

The UltrAspire Alpha 6.0 Race Vest ($150) is the most recent in a line of hydration packs that have been around since 2013. The first version of the vest was well-loved, and 12 years later, this one still lands itself in our Best Running Vests buyer’s guide. This unisex hydration pack is a great medium-sized vest with a thoughtful design, a highly flexible six-liter capacity, great overall comfort, and a smooth ride.

I found this to be one of the most stable hydration packs out there, whether you’re only carrying some fluids and your phone for a shorter daily run or you’ve maxed out storage and added poles in a quiver (not included) or to the rear bungees. The ErgoFit design keeps the stress of a fuller pack off the neck and the load centered a bit lower on the body than many other packs out there, and the MaxO2-Sternum lets you breathe freely with the snug-fitting, bounce-free design. This is still one of my favorite design aspects of UltrAspire vests.

I’m absolutely loving the fact that the hydration bottle pockets in the front are now fully compatible with just about any 500-milliliter soft flask you have, including UltrAspire’s proprietary soft flasks — two of which are included with the vest —and the longer cylinder options common with other brands. Regardless of how you count pockets within pockets to get a final number, there are plenty of options on the pack for all your needs and wants, including a sleeve pocket against the back with a bladder hanger that can hold up to a two-liter bladder and route the hose securely over either shoulder. In my experience, having tested two prior versions of this pack, the Alpha 6.0 is the best thus far. It has an actual weight of 8.8 ounces (250 grams) for a size small.

Unfortunately, the Alpha 6.0 still comes in only three unisex sizes — small, medium, and large — and can accommodate chest sizes from 31 inches to 42 inches. In my opinion, there’s still a need for an extra small and an extra large option. My 34A chest size has the bungee closures on the size small about 75% cinched for daily usage.

UltrAspire Alpha 6.0 Race Vest Construction and Fit

The UltrAspire Alpha 6.0 Race Vest.

The UltrAspire Alpha 6.0 Race Vest is constructed from the familiar UltrAcool Light Mesh that helps to move moisture from the skin and reduce heat buildup. It still feels a little abrasive to the touch, but I always run with a shirt, so it’s not a factor for me. It doesn’t cause pilling to any of my shirts or fleeces, so if you like to run with less clothing on top, you may be just fine.

Two honeycomb mesh panels run on either side of the front of the pack against the body to help with comfort, sweat management, and fit in the closure areas. I find it very effective in preventing chafing on the super-hot days. The closures themselves, called the MaxO2 Sternum design, are two fixed hooks to which you attach a looped bungee cord from the opposite side. It’s pretty easy to do once you figure out the angle to approach the hooks, and it can be done with thin gloves. Though the hooks are fixed, the bungees have a lot of adjustability depending on how full you have the pack. An unobtrusive flat routing loop is also present on either shoulder strap to secure a bladder tube in an easy-to-reach place.

Very soft binding covers all edges of the pack, further promoting skin comfort, especially under the arms and around the neck. All pockets are made with a four-way stretch mesh that excels in keeping contents secure yet accessible and reduces the need for compressive bungees or load management cords. This mesh also enhances the overall breathability of the pack, especially if a solid breeze is swirling. Nothing really impedes the airflow through the pack unless you’ve added some extra Ziploc baggies for waterproofing of electronics or extra snacks.

UltAspire’s ErgoFit design is indeed very comfortable. The S-curve angled shoulder straps remove the load from your upper shoulder/neck junction and move it out and down a bit. This keeps the neck and shoulders moving freely and decreases the strain on my upper trapezius muscles. The length of the pack takes the load lower on the body, which can take a little bit of getting used to with how it hugs the mid and lower ribs. I’ve found the design reduces the overall fatigue a pack can cause later in a race or longer adventure. I have perhaps a longer torso, but I find it very easy to wear.

The fabulous MaxO2 Sternum shock cord system allows the bungee closures to stretch every time you take a breath and recoil to the same place. The load stays secure and snug to the body without the need for over tightening or progressive tightening during a run, and it doesn’t hamper breathing even when powering up steep inclines or pushing the pace on a gentle and super runnable downhill. I wish more brands would incorporate this type of technology, as it significantly enhances the overall pack-wearing experience

I do find this pack to be a little heavier and a bit hotter than some of the very lightweight packs from Salomon and Arc’teryx, but it does seem to be more durable — a plus if you find yourself bashing through willows or wedging between rocks and hard places on a scramble. The Alpha 6.0 is also more stable over varying loads, but if you’re looking for a super minimalist feeling pack, you may prefer something different.

The Alpha 6.0 is a sleeker version than past models while maintaining all of the functions and performance.

UltrAspire Alpha 6.0 Race Vest Storage and Hydration Options

The back of the UltrAspire Alpha 6.0 Race Vest.

The UltrAspire Alpha 6.0 Race Vest includes four pockets on the back of the vest and another eight pockets on the front, including the two hydration bottle pouches. Zippers are employed on two front pockets, ideal for keeping smaller items secure, and across the top of the main stuff pocket in the back. The small sweat-proof magnet-closure pocket sitting above the hydration bottle pocket on the right can hold electrolyte tablets and pills securely and can be operated easily with a finger or two.

I like that most of the pockets are stuff pockets and accessible without too much forethought or coordination. The four-way stretch mesh does a great job of providing enough compression without the need for more cumbersome straps.

Speaking of compression, however, I do miss the external X-crossing bungee on the very back of the pack that I used to love for a quick stash of a lightweight jacket. Luckily, UltrAspire made up for it by improving the pass-through pocket at the very bottom of the back of the pack. The opening is slightly more lateral — angling toward the front — on the pack, thus easier to reach without having to take it off. I can easily slide a thin puffy, fleece, or wind layer here and pull it out from either side for quick donning when the weather makes a sudden shift.

The two bungees on either side of the pass-through pocket are perfect for poles, and the improved position makes them secure at the lower back. I found that there was almost no bounce at all. I do typically take my pack off to stow or retrieve the poles, but that’s more so I don’t catch a toe and do a gravity check while my arms are stuck behind me. If you’re a fan of the pole quiver, this pack is compatible with the UltrAspire quiver (purchased separately) and utilizes bungees at the shoulder to offer more pole storage options. At iRunFar, we don’t recommend storing poles on the front of the pack to reduce the chance of serious injury in the case of a fall.

The back of the pack now has a full-length stash pocket accessible from the top that ends in front of the pass-through pocket that swallows layers, a headlamp, or a first aid kit. At the top of this large pocket is a smaller hanging pouch with a key clip that is ideal for a safety blanket, wallet, and keys. A zipper keeps everything in this section secure, but it does mean that you have to remove the pack to access it. The bladder sleeve lying flush against the back can hold up to a two-liter hydration bladder that is very easy to hook to the hanger at the top. It is compatible with an insulating sleeve, should you have one from a prior purchase, as it is not included with this pack.

The front of the pack is where I keep most of the things I need between aid stations or want easy access to on self-guided adventures. The two 500-milliliter soft flask pockets helpfully have shock cords that fit around the bottle tops to hold them securely. I’d say that unless you have a very flexible neck, you might want to consider taller bottles or ones with straws due to the fact that the pack rides a bit lower than some. Opposite the sweat-proof salt-tab sized pocket with a magnetic closure on the right, there is a drop-in, bungee-tightened pocket on the left side of the harness. The drop-in pocket can theoretically hold a phone securely, but my collarbone isn’t a huge fan of that, so I like it for a few gels or a buff and thin gloves.

Beneath each soft flask pocket is a full-hand-sized stuff pocket with a smaller overlying zip pocket with angled entry. The stuff pocket is my favorite, and although others have noted some minor difficulty accessing these when carrying full bottles, I didn’t seem to have an issue. I struggle a bit more with the restricted opening and surprising depth of the zipper pockets with my fairly sturdy fingers, so I tended to use the zipper pockets for items I needed to access less frequently.

All in all, I love the streamlined design of this pack’s storage and am consistently surprised by how much I can cram into it with no bounce and no neck and shoulder discomfort. The lower-riding rib-hugging sensation is very comfortable but does take some getting used to if you’re coming from the higher-sitting packs more common today.

I haven’t seen any wear, tear, or stretching out of any of the pockets after a summer’s worth of use, and previous renditions of this pack have retained their shape and elasticity exceptionally as well, even after years and multiple family members’ use.

UltrAspire Alpha 6.0 Race Vest Overall Impressions

The UltrAspire Alpha 6.0 Race Vest.

The UltrAspire Alpha 6.0 Race Vest is the best version of this pack thus far, particularly now that most brands’ 500-milliliter bottles are compatible. I’ve had the good fortune of wearing and testing the first and third iterations of this pack as well, and I appreciate how streamlined and stable it has become for a six-liter pack while staying comfortable and secure, whether carrying lighter or heavier loads. I’d re-add the X-crossing bungee on the back of the pack if given the option and throw in a small safety whistle, but it is certainly an excellent mid-size pack and has earned its place in our Best Running Vests guide.

It is worth highlighting that if you struggle with neck and shoulder discomfort from hydration packs as the running and hiking hours stack up, the design and fit of the Alpha 6.0 can be a game-changer. It harkens back to the fit of the packs that first came on scene when I began dabbling in ultrarunning in the late 1990s, but with all of the other features improved thanks to 30 years of industry developement and UltrAspire’s keen attention to detail.

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Check out our Best Running Vests guide to see some of our other favorite hydration pack options.

Call for Comments

• Have you had a chance to try the UltrAspire Alpha 6.0 Race Vest? What do you think?
• What features do you find most valuable in a mid-sized running vest?