These days, it’s not unusual to see runners speeding by with vests full of pockets and a few drinking spouts. Because they make it easy and comfortable to carry water, food, an extra layer, and other necessities for longer runs (usually lasting one to two hours or more), these running hydration vests have become quite popular.

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Here’s a brief rundown of the key features you should consider if you’re shopping for a new hydration vest; continue reading for more information.

A Guide to Selecting a Running Hydration Vest: Four Steps

Select a capacity: Verify that the running vest has enough capacity (measured in liters) to hold items such as additional clothes, food, and water. Most runners require roughly two liters of room for one- to two-hour runs. You should use a vest that can hold two to six liters for runs that last two to three hours. Choose a vest that can hold four to twelve liters for runs that last three to six hours. Additionally, you should have at least six liters—or as much as the maximum capacity that will suit your needs—for runs that last six hours or longer.

Select a reservoir and/or bottles: The majority of vests are pre-assembled with either a hydration reservoir that slides into a rear sleeve or water bottles that tuck into the vest’s front. While refilling bottles might be quicker and easier, sipping from a reservoir while on the go can be easier and usually store more water.

Make sure your running hydration vest fits properly. This will prevent the vest from moving around while you’re running. For the ideal fit, adhere to the manufacturer’s size recommendations.

Seek out other features: Check the vest for breathability, reflectivity, trekking pole keepers, convenient pockets, and an integrated whistle.

Gear Capacity for Running Hydration Vests:

There are several different sizes of running hydration vests, ranging from around two liters to over twelve liters or more. The amount of space required is determined by the amount of gear you want to bring, which is mostly determined by the length of time you anticipate to run.

Many runners use something other than a vest for short runs, say less than an hour, to carry some water, a home key, and sometimes an energy gel. Examples of these items are a portable water bottle and a tiny waist pack. However, if your runs are lasting an hour or more, you should definitely pack a little bit more, such as extra food and drink, as well as a cap, gloves, torch, phone, first aid kit, and map. For many runners, this is the moment at which wearing a hydration running vest makes sense.

Use the table below as a starting point and consider how long your runs usually last to determine the best gear capacity for you. (Remember that factors like temperature, kind of run, and personal taste might affect just how much of a vest you need.)

Using Hydration Vests: Comparing Reservoirs and Water Bottles

Making a decision about how you want to carry your water is crucial when selecting a hydration running vest. The majority of vests are designed to hold water in one of two ways: either in hydration reservoirs that slide into sleeves on the back of the vest, or in water bottles that stow on the front. Whichever you select will depend in part on personal choice. For example, some runners love to drink from a reservoir tube and aren’t concerned by the weight in back, while others just don’t like the sensation of the extra water weight on their backs.

How to Select the Appropriate Hydration Running Vest Size

It’s important to get a running hydration vest that fits appropriately and moves with you; a vest that is too tight might chafe painfully when you’re running. Here are a few methods to make sure the vest fits properly:

As per the manufacturer’s size instructions: To assist you get the perfect fit, hydration running vest manufacturers frequently offer precise size standards on their websites. Examples of body measures they frequently include are bust, sternum, and/or ribcage circumferences, along with a chart that indicates the appropriate vest size based on those dimensions. You should have a decent chance of finding a vest that fits you well if you strictly adhere to these criteria (keep in mind that fit requirements differ from manufacturer to manufacturer, so be sure to check the directions for the specific vest you’re interested in).

Select a snug fit: The purpose of running vests is to restrict mobility during running by fitting snugly. A vest that is too large may slide around, which may be bothersome and uncomfortable, particularly if it chafes painfully (see more about preventing chafing). Look for extra fabric where the vest wraps under your arms or around the shoulders as you try it on. You might want to try a smaller size if it’s loose there. When you inhale deeply, like you would when puffing and huffing up a path, if the vest feels constricting or uncomfortable, it may be too small. To obtain the most realistic feel for fit while testing the vest on at a REI shop, work with a sales professional to load the vest with weight.

Allow for adjustment: Take note of any straps on the vest that may be adjusted, such as those that span your chest or rest beneath your arms. These straps should be roughly in the center of their adjustment range when the vest is on and ready to wear. You may be wearing the incorrect size if they are at either extreme.

Women-specific vests: Choosing a vest made specifically for women is beneficial to many women. Women’s running hydration packs are usually made shorter overall, with more space in the bust and narrower shoulders.

Extra Capabilities for Running Hydration Vests

Numerous features are available for running hydration vests, which can increase their comfort and convenience. When selecting a running hydration vest, have the following things in mind:

Pockets: The majority of vests include many pockets to store regularly used goods like extra layers, gels, and phones. Make sure the pockets are easily accessible by looking at their placement. Ideally, you shouldn’t have to stop moving in order to reach an energy gel or grab a jacket. Think about the pocket closures as well. Important stuff won’t fly out of your pockets when you stumble on the path thanks to zippers, but they’re typically a little more difficult to get in and out of than a flexible pocket.

Reflectivity: A lot of vests have reflectivity built in to make you more visible to other runners using headlamps or to oncoming vehicles while you run at night.

Breathability: Although most vests have a fair level of breathability, if you tend to run overheated, you may want to explicitly check for this feature. Pay special attention to the mesh fabrics that enhance ventilation on the back panel and the straps that encircle the front.

Emergency whistle: On a sternum strap, some vests come with a whistle. If you ever need to let someone know where you are, this may be a very useful emergency tool to have.

Trekking pole keepers: If you enjoy using trekking poles on the trails, you may want to consider wearing a vest with a specific place for keeping them fastened.