A Starter Guide for Fitting Backpacks with Hip Belts (Pt II)

Hey everyone! This week’s write-up is the part II of our backpack fitting starter guide. It aims to cover how to fit a backpack that has a belt support and/or a chest strap to reduce lower back pain. For our part I guide (Backpack Fitting Part I: A Starter Guide for Fitting Beltless Bags) which discusses fitting a regular, grade school style, backpack click here


If you’re like me, you’ll find yourself using your backpacking pack at least a half dozen times throughout the year. There’s nothing quite like hiking down the path with everything that you need for the weekend on your back. It doesn’t hurt that we get to do it in this lovely state! With a little care you can organize your pack to better accommodate the weight and in turn, ease the stress and lower back pain that you will put your body through. I’m embarrassed to say that I’ve been on more than a couple treks where my bag was overloaded and/or improperly organized. Let me tell you that it made the hike a real pain! Thankfully, I have learned the errors of ways and I’m here today to show you how to avoid the same mistakes that I made when I first started using a backpacking pack.

Before we get to fitting, I want to have a brief discussion about weight. Selecting a bag that is the right size for your activity will help to keep your bag as light as possible. For an adult, I find that 30-50L size bags are perfect for the average weekend getaway of 1-3 days. When it comes to kids, you want to take special care not to overload them and therefore should not buy them an overly large bag. If you are planning on an overnight hike, I really recommend resigning yourself to carrying the majority of their weight. They can carry some extra weight with a belted backpack but I would encourage limiting it to about 15% (give or take a few lbs.) of their body weight. Adults can carry quite a bit more than that, but the general rule of thumb is the lighter the pack, the better the hike. Typically a good sweet spot for gear is 20-40 lbs. including the pack and all of its contents. Once a pack starts hitting over 60lbs., you can expect a greater toll on your neck, back, and shoulders. Getting to the lightweight category (<20 lbs.) is even better but may require more expensive equipment and/or leaving some luxury goods behind. In the end, I don’t recommend sacrificing important safety equipment (like a change of clothes) in order to save weight. Lastly, don’t forget to load the bag with most of the weight towards the bottom and back of the pack (closer to your body). This will lower and centralize the center of gravity and make the weight less cumbersome.

Ok, now that we have that out of the way, let’s get to sizing and fitting.

Sizing for packs usually starts with 2 measurements – torso length and hip size. Torso length is measured from the C7 vertebrae (where the bottom of your neck meets the top of your upper back) to the level of the iliac crests (the top of your hips bones). Hip size is measured around the waist by placing a measuring tape around the iliac crests. This process is important to selecting the right pack for you but keep in mind that all manufacturers are a little different in their sizing. It is very important that you try the pack on in person, preferably with a knowledgeable sales associate to help you. It is equally important that you use dummy weights (sand or bean bags are often used in stores) to simulate carrying a load as the pack may feel radically different when loaded. Ultimately, I recommend going to your local or national retailer for fitting and buying.

There are several steps to perform when fitting a backpack with belt and chest straps:

  1. If your bag has a torso adjustment, ensure that it is adjusted to fit your measured torso size. You may have to play a little with this especially if the pack doesn’t have any measurement indicators on the adjustment parts.
  2. Ensure that the belt of the pack hugs the top of those hip bones (iliac crests). I like to start with the top of the crests sitting somewhere in the middle of the hip belt and then I adjust from there. If the belt doesn’t fit around that area, you may need to adjust the shoulder straps and/or the torso length to get the desired fitting. Once the belt is in the right place, tighten the strap until snug (but not overly tight).
  3. Tighten the shoulder straps evenly until they are snug. You should NOT feel a lot of heavy weight around your shoulders – the hips will be carrying the majority of the load. Make sure that the shoulder strap anchor points (the point where the strap connects to the rest of the pack in the back) are an inch or two behind the top of your shoulders. There is no hard and fast rules when it comes to tightening shoulder straps and you may find that you will use a couple of different adjustments over the course of your hike in order to avoid too much pressure in one area or the other.
  4. Tighten the load lifters (the small straps between the shoulder straps and the pack) until they are roughly at a 45-degree angle. It is important that they are not overly tight or loose.
  5. Find your sternal notch by placing your finger in the center of your chest about where your collarbones meet. Ensure that the chest strap is about 1-1.5 inches below that notch. You may have to adjust the strap to get it in the right place. Buckle the chest strap and then tighten it until the shoulder straps are secured and you can freely move your arms and breathe with ease. The chest strap is often overtightened and can cause a lot of problems in the shoulders and chest if not properly adjusted.
  6. As you hike, pay attention to how the pack sits on your body. Make small adjustments periodically – using all of the straps – until you find the most comfortable fit.

There are only so many days left this Summer before we settle into Fall. If you plan on squeezing in a few more backpacking trip like I do, then take care to understand the basics to pack fitting and organization. Just a few small steps before every hike can make a huge difference. Your body will thank you for it and you will enjoy the hike a lot more!


Dr. Kelly