t is important that you carry what you need for the four days (or 2 or 3) as comfortably as possible. Your rucksack should keep the load close to your body so you move as one and avoid backache.

There are 4 main types of sack:

* Day Sack - 18-40ltr with fixed straps and maybe a waistbelt. Only used for carrying waterproofs, food and spare clothes.

* Soft Sack - specialised for climbers and fell runners. Flexible frames, moulded backs, fixed straps and padded waistbelt.

* Framed Sack - All modern ones now have an internal frame. Most have an adjustable back, so the length can be changed to fit your back length. Typically 65-75ltrs.

* Travel Sack - Used for interailing not walking.

It is suggested that 70% of the weight of the rucksack is carried on your hips so the waistbelt is very important. Take time when choosing a sack. If possible, ask to have some weight put into the sack so you can feel the weight distribution.

Once you have loaded you sack you should be able to stand up right with no pull back, as this indicates that the load is not central. To help, pack the heaviest items at the centre of gravity (near the top of the sack).

When fitting a rucksack, there are 4 steps.

1) Fit the waist belt snugly on the hips (not around the stomach).

2) Tighten shoulder straps so that there are no gaps.

3) Fit chest strap if necessary.

4) Adjust top straps so the load is close to your body. These are used for balance as well. When going downhill, loosen them off slightly.

Note: If you sack has an adjustable back, this may need adjusting BEFORE you carry out the above steps. On some models (ie Karrimor SA systems) you adjust the back AFTER you carry out the above steps. If in doubt, ask at the shop.

PLEASE NOTE: Rucksacks are NOT waterproof. You MUST pack EVERYTHING (except liquids) into plastic bags inside your sack.