Consider these 6 tips when choosing a rucksack and you'll be surprised how comfortable it feels.
1. Decide what size rucksack you need
- Smaller day sac (Up to 25 litres). Includes specialist sacs e.g. for fell running and mountain marathons, of a lighter construction with external compression systems to stop your gear bouncing around. Designed to be stable on your back when moving at speed.
- Larger day sac (25 to 30 litres). Look for specialist features you know you will need, such as ice axe loops or crampon straps, if you are going winter walking, or side or lid pockets for easy access to photography equipment
- Small multi-day sac (35 to 55 litres). Useful for single overnight trips in hostels. Also used as a larger climbing / winter mountaineering sac.
- Large multi-day sac (55 plus litres). For multi day backpacking, trekking or travelling. These are carrying the heaviest load so are the ones where it is absolutely imperative for the health of your spine to get the correct fit. Look for a rucksack with an adjustable back system, broad and well padded hip and shoulder straps, and a chest strap.
Take a rucksack that is too big and you’ll tend to fill it and end up carrying more weight than you need. If you get one that’s too small you will have a problem on colder days when you need more gear and either end up going out underequipped, or have bits of equipment hanging off the sac which can unbalance it.
Most people who are regularly in the outdoors will have a selection of rucksacks to choose from depending on the length / nature of the trip and the season.
2. Determine your back length
- Find the spinous process of the C7 vertebrae. This is the most prominent knobble at the base of your neck just above the level of your shoulders.
- Find the iliac crests of your pelvis. You do this by standing with your hands on your waist then sliding your hands down until you find the top of your pelvis. Project a horizontal line from here to your spine.
- Use a flexible tape measure to measure the distance between the two points. You’ll need a friend to help you do this.
3. Don’t forget to sex your rucksack
Many rucksacks are now made in a male and female fit. They tend to allow for narrower shoulders, a shorter back length and wider hips on the female versions. That doesn’t necessarily mean that if you are female you must buy a female specific rucksack. Women with long backs may get a better fit from a “male” rucksack whereas smaller framed men with narrower shoulders should also try “female” sacs for size
4. Go to a specialist retailer
A good rucksack will last for years. It is well worth getting the one that is correct for you. To do this you need to try the rucksack on. Go to a specialist outdoor retailer who has staff trained in rucksack fitting
5. Fit the rucksack to you
- Tighten the hip belt. This should go snugly around the top of the pelvis, not around the stomach. It should be tight enough to facilitate the load transfer to the legs, but not so tight as to be uncomfortable
- Tighten the shoulder straps. Do not overtighten or the hip belt will be lifted upwards
- Tension the load adjusters on the shoulder straps and the waist belt to stabilise the pack
- Fasten the chest strap: this can be uncomfortable especially in women if it is too low. The chest strap should be roughly level with the bottom of the arm pit.
6. Protect your spine by using and handling the rucksack correctly
- Keep the weight down: There is no need to go out underequipped in bad weather, but critically examine the kit that you are carrying and keep weight to a minimum.
- Heavy items at the bottom and close to your spine to reduce the leverage effect on the spine
- Picking it up and putting it down – The easiest way to damage your spine is to lift a heavy weight with a flexed spine and then to twist; this is how most of us pick up a rucksack. To put on a heavy rucksack without damaging your spine see our the advice sheet above.
Disclaimer: The information on this page is written to help you avoid injury. There are many possible causes for back pain and should you have any concerns you should always seek advice from a qualified health professional such as a Chartered Physiotherapist or your GP.





