It is important that when choosing it, you take into account that it molds in the best way to your waist and back so that you can have a good balance when walking.
Let's start with size and capacity:
Size
It's like when you have to choose a clothing size, there are also backpacks for men and women, except that not all brands have different sizes and models.
All bodies are different and mountain backpacks have a back system adjustable to you.
How do you know what size you are?
It has nothing to do with your height but should be based on the length of your torso, from your waist to the base of your neck. Here is a small table to find your size:
Lumbar belt and suspenders
It is the main part, it should not be too high or too low on the waist, but it should be just above the curvature of the lower part of your back and hug the sides well.
The belt serves so that the weight falls directly on the hips and not on our shoulders and spine and thus, our neck and vertebrae are free of the load.
Women's sizes carry the belt slightly higher than men's sizes and prevent the shoulder straps from clogging the chest.
Once the belt is properly adjusted, the straps should rest directly on your shoulders, without them rubbing your armpits or squeezing your arms, make sure they are padded.
Chest belt
This will allow you to have your hands free in case you need them and the backpack does not move.
Frame
It is the part that directs the weight towards the waist, there are frames made of different materials such as carbon fiber, aluminum, plastic, etc. and these influence the weight, but the important thing is that it has an acceptable stiffness so that there can be a little ventilation between your back and the backpack.
Adjustment straps
The belt and the straps have straps that will allow you to adjust the backpack to the trunk of your body so that it is attached to your back and thus compress the weight and you can move freely. These are adjusted once you have the backpack on.
There are more and more models of backpacks made for women, our back length and width is usually shorter than that of men, so we need a narrower backpack.
I totally recommend that you buy the backpack of your gender since as men's mountaineering backpacks are a little longer and this can cause women to get in the way of the upper part of the backpack on the head when turning up and If you wear a helmet, it will annoy you even more (I say this from my own experience, it is horrible not being able to move your head freely to see where you are going up).
Each backpack adapts to the body in a different way, it is worth investing in your comfort and health.
Check capacity
Backpacks are measured in liters and you must choose depending on the weight you want to carry or the number of days that your excursion will last.
10- 30 liters: for day trips
30- 50 liters: for excursions of two to three days
50-85 liters: for excursions of more than three days
You can consider buying a waterproof cover that covers your backpack in case of heavy rain, this can be purchased separately in case the backpack does not bring it and there are also different sizes for any backpack.
Most backpacks are water-resistant to some degree, but sometimes it pays to put a cover over it.
We have to test the backpack
To ensure that the backpack fits you, mount it empty on your back and if the body of the backpack stays straight, it is a good sign.
Once the bolt is tightened, you can ask someone to exert a downward force from the bottom of the backpack, simulating weight. If the belt stays tight around your waist, it's another good sign.
