Ultralight backpacking

Many ultralight backpackers use a tarp tent system where the trekking pole serves as the structure for the tent.

Tents, hammocks, and tarps with bivy sacks are used by long distance hikers to protect themselves from the weather. Of these, tents are the most common. The development of Dyneema Composite Fabrics, and very lightweight silicone coated nylon fabrics have allowed manufacturers to produce very lightweight tents. The lightest tents are single wall, but even some double wall tents are very light weight. To further reduce weight, some tents use trekking poles commonly carried by long distance hikers for their main support. Weight can be reduced even more by using poncho-tarps, or the use of a bivy sack (Alpine style) as the sole shelter.[10] Generally as weight decreases, the skill to safely use a shelter increases.

Reduction in weight of the sleeping system is achieved through reduction of the quantity of fabric used in its manufacture or through use of lighter-weight materials in its construction. Down is a lighter insulation material by volume than currently available synthetic fibers,[3] which will reduce bag weight, but it is susceptible to loft loss caused by moisture.[10] The overall weight of a sleeping bag can be reduced by eliminating superfluous material. An example of this is the use of a sleeping quilt or top bag. A sleeping quilt is a bottom-less insulated blanket which has no insulation on its bottom side, relying on the user's sleeping pad to guard against conductive heat loss into the ground. A top bag is more like a conventional sleeping bag in that it wraps around the user's entire body but the bottom fabric contains no insulation. The idea is that bottom insulation is normally compressed by a person's body weight, rendering any loft in that area useless. Some modern down sleeping bags are through-baffled and under-filled such that the user can shift all the insulation to the top of their body thereby maximizing its potential to retain heat. Ultralight hikers also tend to carry bags rated for warmer temperatures than traditional-weight backpackers, making up the difference on cold nights by wearing insulated clothing to bed, such as a balaclava[3] or an insulated jacket. Proper camping site selection that avoids colder hollows (low points where cold air tends to collect)[3] or that makes use of natural wind barriers such as thick vegetation or cliffs makes up the difference in heat lost by lighter gear.

With a lighter shelter and sleeping system, the backpack can consist of lighter material and a less bulky frame or no frame at all. The common ultralight alternative to an internal frame pack is a frameless pack made of ripstop nylon, silnylon, or Dyneema Composite Fabric (DCF), formerly known as Cuben Fiber, with a carrying limit of 11 kilograms (24 lb).[3] An internal-frame pack can weigh upwards of 2.5 kilograms (5.5 lb) with features such as hip belt stabilizers, lifter straps, sternum straps, and compression straps; ultralight frameless packs are commercially available in weights ranging from 200 to 400 grams (8-14 oz)[10] and can consist of not much more than a sack with shoulder straps, a return to the simplicity of the rucksack. Jardine's book includes directions to make your own "ultralight pack".[3]

Some backpackers choose to make their own gear. Advantages to such an approach include possible reduction of cost and the opportunity to customize the gear to the individual user. Additionally, if a homemade item were to break down, the hiker would be in a better position to repair it. Lastly, commercial manufacturers often choose heavier, more durable material for their products in order to reduce the amount of care and maintenance required of the user (and minimize returns of damaged gear). Given proper care, homemade lightweight gear can last as long as it is needed.

The remaining gear (such as ten essentials and survival kit) carried by an ultralight backpacker follows a similar philosophy of replacing traditional backpacking gear with lighter options. Replacements include:

• Making a fire instead of carrying a stove.
• Light weight alcohol stoves such as a beverage can stove or solid fuel stoves instead of heavier gas stoves
• Single cook pot ("billycan") with a single spoon instead of a traditional mess kit
• No stove and its associated paraphernalia at all, relying on no-cook meals for food
• Trail running or running shoes instead of hiking boots, and lightweight nylon socks instead of heavy wool socks.
• The minimal amount of extra clothing safely possible.
• Plastic or silnylon bags instead of the conventional (and heavier) packaging that a traditional backpacker might carry.
• A razor blade or a light 1 ounce (28 g) small pocket knife instead of a heavy Leatherman style multi-tool or Swiss army knife.
• Chemical disinfectant water treatment (iodine tablets, chlorine dioxide) instead of heavier water filters.
• Plastic Soft drink or soft plastic bottles instead of heavier nalgene or lexan bottles or Hydration packs.
• A 0.25-ounce (7.1 g) LED light instead of a heavy flashlight or headlamp.

A 1.5-litre (1.6 US qt) bottle of water. The water itself weighs 1.5 kg (3.3 lb)

Water can be a significant contributor to pack weight because moderate activity in a moderate climate requires 2 litres (2.1 US qt) of drinking water per day,[11] with a weight of 2 kilograms (4.4 lb). When traveling through an area with many springs and streams, some ultralight hikers can carry as little as 350 millilitres (12 US fl oz) of water, or none at all, provided the hiker is confident on how far away the next reliable water source is and the expected weather conditions, but in other regions hikers must carry all their water requirements, and can only minimize the container weight.

Some ultralight hikers reduce the weight of water purifying devices, carried to prevent waterborne diseases such as Giardiasis, Cryptosporidiosis and dysentery, by carrying lighter disinfectants as opposed to filters or Ultra Violet (UV) treatment devices. Some hikers carry no filtration device at all.

The Smartwater bottle is popular for use in ultralight backpacking because it's relatively light and strong, and makes efficient use of space.[12]

A common variety of trail mix made out of peanuts, raisins, and candy coated chocolate, around 4.8 kcal/gram[13]

After shelter, a sleeping system, the backpack itself and water, food is the biggest contributor to pack weight and an area where substantial gains over traditional backpacking can be made.

The Basal metabolic rate requirement of food calories (one food calorie is 1000 heat calories, thus sometimes labelled kcal) is approximately 1000 per day per 100 pounds of body weight.[11] However exertion in the form of hiking consumes additional calories; for example the standard US Army field ration is 4500 kcal per day for strenuous work.[11] Thus depending upon type of food an average hiker carries, a hiker requires approximately 2 kilograms (4.4 lb) of food per day.[14] Ultralight techniques can substantially reduce this weight, Jardine suggests 2.5 pounds (1.1 kg) per day for thru-hiking,[3] Jordan suggests 1.25 pounds (0.57 kg) per day (at 125 calories per ounce, 4.4 calories per gram) for a 3-season 3-day backpack.[1][15]

Many foods can be dried or dehydrated to reduce water weight. Dehydrated meals can be purchased or dehydrated at home. On the trail, rehydration can typically be performed by cooking in hot water. Some ultralight hikers reduce weight by not carrying a stove and rehydrating food in a container with water (although this method requires more time to rehydrate than the traditional cooking method). For example, Ramen noodles, dehydrated refried beans (in powdered form), or dehydrated hummus can be put in a ziploc bag or lightweight microwave disposable plastic container with water to rehydrate. Oats (groats or rolled, granola or muesli) and barley also become soft enough with soaking to eat uncooked as a raw food. Tsampa is a simple, bland and lightweight dish made from flour, and has been used for centuries by wandering Tibetan monks.

Weight in the form of food can also be reduced by choosing foods that have the highest ratio of calories per weight. Proteins and carbohydrates have approximately 4 kcal per gram whereas fat has 9 kcal per gram,[16] thus carrying foods high in fat content can reduce weight, such as:

• Peanut butter (5.89 kcal/gram[11])
• Nuts (Pecans are 6.87 kcal/gram,[11] toasted coconut is 5.92 kcal/gram[17])
• Pemican (5.7 kcal/gram[18])
• Dried whole egg (5.92 kcal/gram[11])

Clarified butter (anhydrous), which stores well unrefrigerated, is almost pure fat (8.76 kcal/gram[19]), thus about 4,000 kcal per pound; however, it is also a potent bear attractant.

Energy bars on average contain more protein and carbohydrates than fat, similar to a fig newton (3.68 kcal/gram), which lowers their calorie to weight ratio relative to other choices.[20]

A captive bear tests a food canister

In some parts of the United States an approved bear-resistant food storage container is a required item for hikers, which will add between 1 lb 9 oz (710 g)[21] and 3 lb 2 oz (1.4 kg) to the base pack weight.[22] These areas include parts of Yosemite National Park,[23][24] Rocky Mountain National Park and the Eastern High Peaks Zone.[25]