How a Running Vest Should Fit (Complete Guide)

Running vests are one of the best gears you can have if you like running long distances, especially on trails. It allows you to bring food, water, and valuables without the annoying bounce of a backpack. But for it to work, it has to fit you well.

The question is: How should the running vest fit?

Running vests should feel snug whether it’s fully packed or empty. It should not move around when you’re running but it also shouldn’t limit chest expansion and torso movement. 

Ahead, we will talk about everything you have to know in choosing the perfect size. I will also give you some tips when buying online as well as what you should do when you’re in between two sizes.

Why running vests need to be snug

Have you ever tried running with a backpack? Have you noticed how annoying it is when it bounces around or falls off your shoulder? That doesn’t happen when you’re wearing running vests. 

Running vests are designed to move with your body as one. It should feel just like another layer of clothing but with storage.

Therefore, they need to be snug to keep them from bouncing around and throwing you off your stride.

How tight should a running vest be?

All points of the running vests should maintain contact with your entire body.

However, it shouldn’t be too tight to the point that it restricts chest expansion and upper body movement. You should be able to insert a finger and slide them in between the vest and your body.

This indicates that there is still room for taking a deep breath or for muscle contraction.

The straps should be aligned and symmetrical. When they’re too close to each other, it indicates that the vest is too large and when they’re far apart, it indicates that the vest is too small. 

Tips on how to fit a running vest

Tip #1: Measure your chest size

Before you go into the store, measure your chest size to get an idea of the sizes you should choose from. 

This will narrow down your choices to 2 sizes instead of trying to fit all different sizes of vests. 

Tip #2: Try it on fully packed and unpacked

A fully packed hydration vest will feel and fit differently than an empty one. So make sure you fill the hydration vest before you decide on the size.

Stuff the vest with clothes, water bottles, or ask the store if they have a hydration bladder and soft flask you could fill. This will give you an idea of how it would feel when you’re running on the trail.

Tip #3: Move around

Once you’ve filled the running vest, test it out by jogging and jumping in place. Notice how you feel when you’re moving with it. Take note mental note of the bounce and compare it with a different size or brand.

Tips when buying online

Tip #1: Always refer to the sizing guide

Most manufacturers have sizing guides and sizing recommendations based on your height and weight. Make sure you check those out.

Tip #2: Don’t remove the tag right away

Once the package is delivered, do not remove the tag. This will ensure that you are able to return the package if it doesn’t fit you well. 

Tip #3: Try it on but don’t sweat on it

Before using it for a full run, try it on and see how it feels.

Once you’re satisfied with how it feels, that’s the only time you can remove the tag and consider it yours.

By the way, if you’re looking for a good running vest, check out the Salomon Active Skin. I like them because they feel really snug and there’s a lot of easy-to-reach storage for your valuables.

I’m in between two sizes: Should I size up or down?

There will be such instances where you’re size is in between two sizes. So what do you choose?

This happened to me when I was buying my running vest online. I really had a hard time trying to find out what size I should get. But nevertheless, my decision came down to these few pointers:

Body goals

Say you’re in between a medium and a large. Choosing medium means you’ve maxed out the size of the running vest. It will be snug for sure but it also has a risk of being too tight. 

On the other hand, choosing large gives you a little more adjustability, but risks being too loose. 

When you’re in this situation, consider what you’re more comfortable doing. To try and gain mass by building muscle, or lose some by shedding off fat?

In my case, I wanted to build more muscle so I chose to size up. Luckily, the large fitted me perfectly.

Closest size

If you’re not trying to gain nor lose weight any time soon, go for whatever’s closest to your chest measurement. 


In case you are able to try both sizes, fill it up and try it on. See which is more comfortable and natural to you.

Final Thoughts

The worst thing that could happen is a running vest that bounces around when you’re running or a vest that restricts motion. To avoid that, make sure to follow the tips I laid out in this article.

Nicho Mauricio

Running wasn't always my favorite sport. I was a CrossFit athlete and I loved every bit of it. But since the pandemic began, I was forced to stay away from the gym and train at home instead. Things got boring. That's when I decided to trail run with my friends. I instantly got hooked. So I started training and researching all things running. As a beginner, I want to buy only the best running gear and do only the best practices. This blog is where I share what I've learned in my journey and my experiences as a runner.

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