How to Correctly Size Your Backpack (and not regret later!)

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Once one has decided on the genre of the journey, the items to carry and the backpack materials one shall need, the next step includes sizing a backpack.

All other steps apart, this one finds its higher priority due to the direct effect it has on the backpacker.

Many a time, one does come across people carrying an oversized or undersized backpack.

This happens usually due to lack of knowledge regarding choosing the right size and sometimes also because of the lack of a good backpack to carry what is needed.

Both of these issues can be sorted by getting oneself familiarized with some theory regarding sizing a backpack.

Backpacks come in different sizes, to accommodate a lot many travel items.

One thing that needs to be registered with certitude is that the size of the backpack must be such that it holds the necessary items along with having some vacancy for a little more.

How to Correctly Size Your Backpack (2)

What All Matters While Sizing a Backpack

Some of the most important things that matter while sizing a backpack –

Backpack volume

The duration of a trip can be used to estimate the volume of backpack one needs.

Bigger backpacks are also called “overnighters”. They range from about 20 liters to 110 liters. These numbers are obtained by calculating the total volume covered by all closed compartments in a bag.

  • On a short one day or half day trip, one can make use of any backpack that ranges from 30-35 liters.
  • Trips that include travel to cold places need backpacks with higher volumes, about 40 liters, for the same duration. As the duration increases, very obviously the volume of backpacks increases.
  • A 4-5 day trip will require a backpack that has a maximum of 70 liters. People who want to set off on expeditions might need backpacks that are sized at about 110 liters. When on such expeditions, it is also advised that one contacts a professional guide, to get more inputs as to how the volume is to be managed.

Your Torso Length

A backpack needs to also be proportionate to one’s body. It is true that the back is the strongest part of the body and is capable of supporting a lot of weight.

But, one needs to also ensure to not injure their back, in pursuit of loading more luggage for their travel. Backpacks come in three size categories, small, regular and large.

People with different torso length should ideally use the category of backpacks, they fit the description for.

Torso length is a parameter that plays a pivotal role in establishing the size of the backpack one’s body can handle, without much strain. This parameter has almost nothing to do with the height of an individual.

A comparatively shorter person can very well have a torso length measured to be greater than their taller counterpart.

In order to calculate the torso length of an individual, we need to establish definitions of two terms, top, and bottom.

  • Top: When we bend our head downwards, there is a bony prominence that inches out right below the neck. This is the C7 on your vertebra or the 7th cervical on your vertebra. This point shall be considered as the top for torso length measurement.
  • Bottom: When we hold our hip, we essentially cup a bony prominence called the iliac crest. This must be held with both hands having their thumbs directed towards each other. An imaginary line that joins both thumbs is said to form the bottom of the torso.

Now we define the torso length as the length measured from the top to the bottom. Chances of toppling or hurting one’s back get higher if the following backpack size specifications are not met.

  • Small- These are for travellers with torso length up to 18 inches.
  • Regular- These fit those travellers whose torso measures up to about 20 inches.
  • Large- These bags are made for travellers who have a torso length greater than 20 inches.

If it so happens that the individual is found to be on the cusp of two sizes, the smarter thing to do would be to go for the bigger size of the backpack.

Also, it is always better to take a look at the size chart before buying any backpack, since, different brands may define the above mentioned three sizes differently.

Backpacks on the higher end of the price strip, come with a suspension to make adjustments to the torso length.

Just in case, there isn’t any, the following adjustments can be made to increase comfort.

Basic Adjustments

These include the initial few adjustments that need to be made to the backpack’s shoulder and hip belts.

  • Hip Belts- The hip belt must rest comfortably on the iliac crest. It must not be very tight though.
  • Shoulder Belt- The shoulder belt’s anchors must be placed on the shoulder blade, which is about 2 inches below the top of the shoulder.

Final Adjustments

These are the extra adjustments that can be made to further increase the comfort of carrying the backpack.

  • Sternum straps – The straps that are present on the shoulder belts are movable. These must sit right on top of the chest, about an inch and a half below one’s collarbone. The purpose of these is to keep the shoulder belts pulled inwards, ensuring that they do not interfere with normal arm movement. Care definitely must be taken to not tighten them beyond a point wherein, one feels uneasy to breathe.
  • Load Shifters – These are one of every backpacker’s favorite adjustments. They are those straps that additionally connect the shoulder belts to your backpack. These take care of the angle at which your backpack is inclined when propped up against your back.

Ideally, the load shifters need to be at 45 degrees outwards, keeping the backpack almost upright, with a slight tilt towards one’s back.

Always do remember that the whole weight of the backpack needs to be evenly distributed throughout the back and must not be left concentrated on the poor shoulders alone.

This will help one to carry their luggage for a longer duration on their backs without much fatigue.

Daypacks with padded or contoured back support are a blessing to the traveller, since, they cushion the back from being directly hit by the weight.

The material used to support the back, allow air circulation without which, the back shall be left damp with sweat.

The genre of one’s travel plays an important role in being prepared with the kind of weather conditions and activity that a backpack may be subjected to.

If it’s a hike or anything similar to it, backpacks that are made for rough use and have a high resistance to abrasion, is an all-weather resilient, can accommodate all the utility items and has a comfortable strap system to help carry it around with ease, is preferred.

While on a trek, adjust the straps after about 10-15 miles, when there is an onset of fatigue. Keep alternating tightness between hip belts and shoulder straps.

How to Pack a Backpack (the RIGHT Way!)

Now that all has been said about sizing a backpack, why leave out the main technique behind packing one!

While packing a backpack, it is important to pack it in an efficient manner such that, items are available and handy when needed. One shall not find the need to dig through their backpack or empty the whole bag, in pursuit of fishing one item out.

Hence, in order to achieve the level of efficiency that has been spoken about, we shall divide the backpack into three layers and pack as instructed below.

  • Bottom Layer – This layer is the first to be packed and the last to be unpacked. Hence, this layer is bound to include items that one shall not need when on foot or pronto! An example of items that make it to this layer would be a few heavy tools.
  • Middle Layer – This layer is the next to be packed. It is a more frequently accessed layer of items. One may need these during a pit stop or so. Food items, stove setup and clothes generally constitute this layer.
  • Top Layer – This is a layer that contains all the high priority stuff. The kind of items that one might require when on the move, like, a first aid kit, toiletries, a spare pair of clothing or even a raincoat.

Apart from these three layers, the outer compartments of the backpack can be loaded with utility items like maps, compass (if anyone still uses one of these), torches, water bottles and bug sprays.

Surely this definitely would be one effective way to pack a backpack!

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