Running Pack Buying Guide

Run the Wild guides Karin and Simon break down everything you need to know about running backpacks and vests before you buy.

Oh, how things have changed. I first started to run to work around 2004, carrying all my kit in the free rucksack that work had given me when I first got the job. The run was only 2.5 miles each way, and if I ensure that the zip was closed on the side of the bag, as opposed to the zips meeting at the top, I stood a reasonable chance of reaching work without my clothes strewn across the streets of East London. I tightened the shoulder straps as tight as they would go, and then tied the excess tails across my chest. The result was a vaguely functional, and only vaguely uncomfortable running pack!

Fast forward 6 years and I was in the market for a running pack once more, this time to help me carry 7 days supplies across the Sahara Desert for the Marathon Des Sables Race. Thankfully the running pack market had already grown substantially, and you could now buy bags which utilised storage spaces on both the front and back of the packs, as well as multiple compartmented areas as opposed to one large cavity, and an increase in adjustable straps.


My now husband was also running the MDS, and had opted for an Aarn pack, a sturdy design which held tight across the chest. He swore by the bag, but once I tried it on, I instantly felt my breathing was restricted, and this would not be the bag for me. I opted for an OMM 20ltr, which sounds large for a running back, but served me well in carrying all my food and supplies, as well as sleeping mat and sleeping bag. As my food supplies decreased as the week went on, I simply allowed my sleeping bag to expand in the space available, so the bag never felt like it was rattling around.


Other tent mates of ours had opted for much smaller Raidlight packs, thinking that reduced capacity would mean a tighter hold and less bounce, but also meant each morning was a battle to get everything stowed away. In the event of a packing error, where a necessary item had in fact been packed away, their restrictive size meant that everything had to be unpacked to find said item, whereas I smugly could have a rummage around in my much larger bag.


Fast forward another 9 years and my pack requirements are typically for single day events now, but still with the capacity for kit to see me through consequential weather systems such that we see in the Alps. Both physical differences between individuals, and the different purposes the bag must serve are the starting points for any running pack buying guides, but here are a few things to think about:

What capacity does your bag need to be?

Depending on where you are running, and how long for, the capacity of a running pack will vary from around 2ltrs at the very low end, up to around 20ltrs at the very upper end which is already moving towards fast packing (a combination or running and walking) or alpine adventures. Beyond this and you start entering the territory of general hiking packs, which can be multi-functional but their weight becomes cumbersome and they generally don’t snuggly to your body, which means you have additional pendulum affect from the bag as you run, which puts you off balance and makes for a less comfortable and smooth trail run. 

Do you need your pack to hold more than just water and essentials?

My running may vary from 5K speed efforts on the road, to big days out on the trail, and whilst it would be nice to have a dedicated pack for every type of run, practicality means I won’t. For this reason, I run with 2 packs, a 5ltr pack and a 12ltr pack. This spread hasn’t left me wanting so far. Remember that a small pack will not suffice for a big day out on the trails, but a big pack of 12ltrs will be able to do both, albeit with some extra fabric weight on those shorter runs.

Hydration Systems:

Hydration can be carried with in a single bladder, or via bottles, whether these be soft flask or not. Many packs have the capacity for both, but smaller packs will likely have more limited space for front held hydration. Soft flasks are now available down to 150ml size, giving you greater options to mix and match. Soft flasks have the advantage of being much more flexible in their use, for refilling or indeed varying what you fill them with, so I often run with one filled with water and the other electrolytes. In the Alps it’s great to have a soft flask spare whether you run with a bladder or not, as it’s easy to refill from a stream or water fountain. The other advantages with soft flasks are that they are easier to clean and dry out, don’t leaks so easily and are much easier to monitor your usage and similarly how much water you have left! 

Vest or Backpack?

I have referred so far to running packs, but realistically many of the bags on the market today are in more of a vest format. These hug the upper body with elastic bungee systems that hold the bag in place, or straight forwards chest clips. The vests are surprisingly comfortable, but I do find with a very weighted bag, there can be a bit of extra bounce, which can be reduced by spreading the load out as much as possible across the whole of the vest (front, back and sides). The base of the vest typically is in line with the bottom of the rib cage, as opposed to on a backpack which reaches the hips. This really is personal preference though, so try both styles out and see what works best for you. Many packs are also available in different sizes, so do have a play around. A vest top tends to open up your chest area more, which helps with breathing. I have a fairly long body, so prefer to have a longish pack, but I really dislike straps that tighten across my stomach. I also often run in a vest top, so have to be very careful about rub points around the neck and shoulder.


Unless you do have a bag for very occasion (this is trail running, not a fashion show after all), some adjustability will be needed to reduce the movement of the bag on the body, regardless of what is packed in. Adjustable straps should be easy to use, but also easy to keep out of the way of moving body parts. There is nothing more annoying that a stray strap constantly flicking against your arm. Many packs have little areas the straps can tuck back into once tightened. Also check to see whether the bag is sold in a female or male fit, does it come in different sizes? All these factors will make the bag more comfortable and therefore your run more enjoyable!


When out for longer runs, your kit will likely be split into a few categories: things you need access to regularly, things you need access to occasionally, things you probably wont use at all, but need to carry just in case, and then things that due to their size or weight must be carried in a certain place. This takes some trial and error, but a pack which has a few separate front pouches is invaluable for longer events. It’s worth practising this strategy of packing and keeping it the same once you have found the most efficient packing formula, that way you know where everything is at any point, perfect as a racing strategy. I personally always like the security of having at least one pocket which has a zip for my phone, keys and credit card, and one which is water resistant at least. Depending on what nutrition you use, you probably will find you don’t want your used gel packs or chocolate wrappers in the same pocket as your first aid kit, so have a think about where you will keep your rubbish too. Some packs even have a small waterproof open topped sack within another pocket, to act as a small bin. What a great idea! 


On longer races I like to have access to at least 4 pockets on the front of my pack, 2 which I use for soft flasks, 1 for food, and 1 for my phone, and then at check points I rotate my nutrition, and dispose of any rubbish. I don’t want a battle to wedge things into the pack. Tired hands and arms mean I want this process to be as easy as possible. The best packs allow you to access most of their stow space whilst on the move, try it on and check what compartments are accessible when the bag is fully on, or just over one shoulder.


Have a think also if your pack needs to have the capacity for add-ons. This may be a quiver to hold running poles, or a loop system at the base of the pack, or straps across the front. It may be a loop and strap to hold on a small ice axe if you are in icy conditions. It may be the ability to attach on a sleeping mat for multi day events. A flexible pack can cover you for numerous scenarios and reduce the cost of having to buy a different bag for each event. I have been known to sew on extra bits and pieces to a bag, but with all the improvements this getting less and less necessary.


I have found that looking after my packs also makes them last a lot longer. The zips on even high-end bags will get stiff if the sweat, mud and sand is never washed out, so make sure you do occasionally clean all your kit properly. Since packs are made of lightweight mesh and elasticated cords, they are more vulnerable and therefore less durable than a military Bergen! However, if you look after it, there’s no reason why it can’t last for 5 years or more, and many manufacturers have a free or paid for mending service, which helps your pocket and saves the planet! Check out their policy on mending and also whether some items are replaceable.


I have neglected to mention it so far, but don’t feel you have to spend a fortune. Many of the cheaper packs on the market actually offer a very good compromise. The 5ltr pack that is my most frequently used pack, is not expensive but my larger running vest is more expensive. I would like to say emulating Kilian Jornet’s kit will make me run more like him, but I think that’s a little wishful. However, the amount of thought and design features that have gone into trail running packs has made a significant difference to their comfort and utility and this is why they are not always that cheap. They have also got a lot lighter and this means you pay more! Light is right but the price will always increase as a result. However, a running pack is an investment, if you enjoy wearing it, you will wear it. It will keep you warm, hydrated, fed, and help out in emergencies (what you pack in it will!) and it should last a lot longer than your trail shoes. 

The last thing you need to think about is the colour of your bag, but I’ll leave that to you! 

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Karin Voller is a Lead Runner for Run the Wild - the UK’s first premier, dedicated trail running holiday adventure company. Operating in the UK and the Alps, they deliver holidays that combine the sense of 'team' from mountaineering, with the thrill of trail running in wild places. Karin is an experienced trail and ultra runner with a marathon PB of 3hrs 20mins. She is also a qualified Leader in Running Fitness.

Simon James is the founder of Run the Wild - the UK’s first premier, dedicated trail running holiday adventure company. Operating in the UK and the Alps, they deliver holidays that combine the sense of 'team' from mountaineering, with the thrill of trail running in wild places. Simon is a keen trail runner and marathon runner with a PB of 2hrs 37mins. He is a qualified Leader in Running Fitness as well as International Mountain Leader and offers treks in the Alps.

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