If you’re serious about running, you’re serious about hydration. The Adv Skin 12 from Salomon is our testers’ stand-out running hydration vest, providing ample capacity for both liquids and gear and an unobtrusive fit for long days on the trail or road. Designed as a performance-driven alternative to the brand’s more entry-level Active Skin line, the Adv Skin vests transition well between demanding training and goal races.

This updated, 12-liter version of the vest is sleeker and closer fitting than the much-loved previous version. The Y-shaped SensiFit™  design was developed to hug the body (preventing unwanted jostling) while allowing the wearer to move fluidly. Some customer-reviewers took issue with this lower-profile update, finding the fit less forgiving. However, our testers—who have decades of experience running long and arduous distances in the mountains and on the road—celebrated the changes. (We tested both versions, and glowing feedback was consistent.)

California-based tester Dari S. used the “soft, thin, yet sturdy” vest during marathon training, including on an 18-mile road run. Logging a total of 45 miles in the vest, Dari found the Adv Skin 12 to be the most comfortable vest she’s used, calling it “a second skin” and reporting “ZERO chafing” on her long runs.

Seattle-based tester Kai P. and REI product copy editor and tester Yitka Winn (who models in the vest in the photo below) were each impressed by the vest’s high-quality material and echoed Dari’s sentiments about fit. Winn, who logged a whopping 175 miles in the vest, including a 100-mile race, notes that the unisex and women’s versions use different size charts. A women's fit may be more comfortable for larger-chested runners; Winn advises measuring your chest circumference and consulting the designated chart of the version you prefer. (See Buying Advice for more on fit.) Buy unisex version. Buy women’s version.

Everything you need, but nothing extra—that's the mantra behind the SalomonAdvanced Skin 5 Vest, a sleek option for runners looking to move fast with minimal weight. A nylon-elastane construction contributes to a snug fit and helps reduce dreaded bouncing. "It didn't matter how many layers I wore, or if I was in a tank top," reports one tester. "It stayed put and never chafed." The slim design also features bungee-cord-like chest straps that offer a more secure fit when compared with traditional clip straps. Tradeoff: Some felt the close fit rested too high on the back of their neck.

The Advanced Skin has six pockets plus the main compartment, fewer pockets than other vests on this list. But that isn't necessarily a bad thing. Our testers reported ample stowage for runs lasting anywhere from 2 to 14 miles. That's thanks to the careful design, which includes four front stretch pockets; one large, open-topped main back compartment with a smaller phone-sized pocket; and one kangaroo-style pocket on the lower back.

The pockets are easy to access. "I could reach back and stuff my windbreaker into the main compartment without breaking my stride," reported one tester after a 13-mile day in Golden, Colorado. A compartment on the back can accommodate a 1.5-liter hydration bladder, which is not included. That said, two front pockets easily stash the included pair of 500-milliliter soft flasks, comfortably positioned to sip on the go. [Editors' Note 5/2/2025: This vest comes in an updated version, which we are currently testing.] Buy tested version here. Buy updated version here.

If the thought of carrying a vest makes your shoulders ache, the UltrAspire Momentum 2.0 may be for you. This vest ditches the hydration bladder in favor of two bottles positioned in a V-shape on your lower back—a game-changing innovation that shifts the water weight to your hips. Magnetic clasps in the pockets prevent the bottles from shaking out while you jitterbug on the trail. "I wondered when the bottles would pop out, but I never lost one," reports one tester. "Fully loaded, it released tension on my back during longer runs." The bottles are relatively easy to grab on the go, though the setup took some getting used to for testers used to running with a hydration bladder.

Testers agree the Momentum 2.0 is "supremely comfy," thanks to its S-shape strap system with a wide fit at the neck and a taper in the mid-torso to help reduce underarm chafing. Nine pockets (including one shoulder pocket designed to fit a phone) swallow gear for any run under three hours. Going farther might be pushing it, though: Our New York-based tester wished for one more large, zippered pocket on a challenging self-supported long run.

The Momentum 2.0 is the only vest on our list that isn't compatible with a bladder. It does hold four water bottles—two 550-milliliter hybrid bottles slide into the back holsters and two of the brand's UltraFlask soft flasks can sit up front. (The brand recommends using its own flasks and we agree, as other soft flasks seemed to jostle out). None of the bottles are included, but we still think the Momentum 2.0 is a killer value. Buy here.

Hydration vests aren’t cheap. This handy piece of gear is designed to do several things well: Hold and dispense liquid, pack gear, accompany you for miles of high-impact exercise on a variety of terrain, and fit your body in such a way that you don’t feel the burden of all that you carry. The Swiftland 5 from REI Co-op manages to do that just for under $100.

This vest has been put through many rounds of testing, since REI Co-op product designers sent the Swiftland 5 out for trail testing during their development process. Our own Expert Advice testers, who tested the vest after it was released on the market, enjoyed the Swiftland 5 for its ease of use. A compression fit system includes sternum and torso straps that allow for small adjustments. There's plenty of storage: two front pockets that will fit your smartphone or satellite phone as well as bottles (not included) and snacks plus rear zipped and stuffed pockets for extra layers and, yes, more snacks. The vest comes with a 1.5-liter hydration reservoir, which REI product copy editor and tester Yitka Winn (who models the vest in the photo below) found perfectly integrated into the vest. “Extra kudos for the very helpful ‘Stop the Slosh’ graphic tutorial printed on the inside of this pack,” says Winn. “Brilliant!”

The fabric on the Swiftland 5 won’t feel as luxurious as some of the pricier packs in this guide, but our Maine-based tester Kalim A. found it comfortable, and had no problems with chafing or snagging. Our California-based tester Dari S. agrees, calls it a solid “no frills” pack with amble gear storage capacity for long runs, though she did find it harder than our other testers to find a snug, chafe-free fit. As such, the Swiftland 5 may be ideal for those who fall squarely within the sizing specifications for the vests—if you’re between sizes, consider sizing down or upgrading to one of our other picks. Buy women’s version. Buy men’s version.