Ultralight backpacking

A bivouac (using a bivy sack) in winter at Benediktenwand, Germany

Ultralight backpacking is a style of backpacking that emphasizes carrying the lightest and simplest kit safely possible for a given trip.^[2] Base pack weight (the weight of a backpack plus the gear inside & outside it, excluding consumables such as food, water, and fuel, which vary depending on the duration and style of trip) is reduced as much as safely possible, though reduction of the weight of consumables is also applied.

The terms light and ultralight commonly refer to base pack weights below 20 pounds (9.1 kg) and 10 pounds (4.5 kg) respectively, however definitions of base pack weights differ within the lightweight/ultralight backpacking community. For instance, some people (such as backpackers outside of the USA) prefer a metric set of terms, with lightweight being under 10kg and ultralight under 5kg. Traditional backpacking often results in base pack weights above 30 pounds (14 kg), and sometimes up to 60 pounds (27 kg) or more. Enthusiasts of ultralight backpacking sometimes attempt super-ultralight backpacking (SUL) in which the base pack weight is below 5 pounds (2.3 kg) and extreme-ultralight backpacking (XUL) in which the base pack weight is below 3 pounds (1.4 kg).

History

Ultralight backpacking was popularized by rock climber Ray Jardine, whose 1992 book PCT Hiker's Handbook,^[3] later retitled as Beyond Backpacking in 1999,^[4] laid the foundations for many techniques that ultralight backpackers use today. Jardine claimed his first Pacific Crest Trail thru-hike was with a base pack weight of 25 pounds (11 kg), and by his third PCT thru-hike it was below 9 pounds (4.1 kg).^[4]

An early pioneer was Emma "Grandma" Gatewood, who thru-hiked the Appalachian Trail in 1955 with only a duffel bag containing an army blanket, a plastic sheet, an umbrella, and other very simple gear much lighter than the heavy equipment common among thru-hikers in those days.^[5]

Philosophy

By carrying lighter and more multi-purpose equipment, ultralight backpackers are frequently able to cover longer distances per day with less wear and tear on the body. This is particularly useful when thru-hiking a long-distance trail.

The first way to reduce weight is by omitting unnecessary items. This often includes camping luxuries such as camp chairs, coffee makers, electronic gadgets, multiple items of clothing, etc. This is the initial step taken by any backpacker seeking less weight on their back.

The next method is reducing item weight. Modifying items to reduce superfluous weight, such as removing the handle from a toothbrush or cutting tags off of clothing is one example of reducing an item's weight. Replacing items manufactured using heavy materials with items made from lighter ones will help as well. For instance, Ripstop nylon can make a much lighter pack than canvas material. The fabrics Silnylon, spinnaker sailcloths and spectra-woven Cuben Fiber (UHMWPE) are regularly used in ultralight applications for their low ratio of weight to surface area. Mountain Laurel Designs offers many types of Cuben Fiber ponchos and shelters in cuben fiber and has been manufacturing cuben fiber backpacking products longer than any other company.^[6] Exchanging fully featured items for minimalist (and therefore lighter) items will save weight as well. For instance an inflatable sleeping pad is more feature-rich and weighs more than a closed-cell foam pad, yet both serve the same purpose. There are many options, so reducing item weight has innumerable choices.^[4]

Field-expedient poncho shelter

The final method is to use multi-purpose gear: one piece of gear which serves the purpose of two, thereby theoretically cutting the weight of the item in half. For example, a lightweight rain poncho which is modified with tie-outs (or tied out with sheet bends) also serves as a tarpaulin shelter. All these efforts can result in base backpacking weight that is under six pounds (3 kg), which was the weight of Francis Tapon's backpack during his round-trip on the Continental Divide Trail.^[7][8]

According to Ryan Jordan:^[9]

The poncho-tarp is probably the lightest possible combination of shelter and raingear that can be carried by the ultralight backpacker.

Another example is an insulated sweater or jacket used in conjunction with a lightweight sleeping bag which boosts the efficiency of the lightweight sleeping bag while remaining a useful clothing item. By using an insulated sweater in conjunction with a lightweight sleeping bag a warmer rated sleeping bag may be made appropriate for the current weather. Warmer weather sleeping bags tend to be lighter and more compressible than colder weather sleeping bags.

Base pack

"Three Heavies" or "Big Three"

The rain shelter, sleeping system, and backpack are considered to be the three major items carried by backpackers. Consequently, reducing the weight of these will reduce overall pack weight.^[10] In ultralight backpacking the weight of the big three is reduced.

The most common rain shelter in use is the tent, but these are relatively heavy due to a number of reasons. They are often designed from two layers of fabric (to address the internal condensation problem), often require the use of metal poles, stakes, and sometimes include a separate ground cloth to protect the tent bottom. Replacing a double-wall tent with a simple tarp and bivy combination will reduce not only weight but also volume carried in a backpack. Other methods to reduce shelter weight include single layer tarp tent hybrids, hammocks, poncho-tarps, or the use of a bivy sack (Alpine style) as the sole shelter.^[11]

Reduction in weight of the second of the big three, the sleeping system, is achieved through reduction of the quantity of fabric used in its manufacture or through use of lighterweight materials in its construction. The use of down as an insulation material which is lighter by volume than currently available synthetic fibers^[4] will decrease bag weight but alternately suffer from its susceptibility to loft loss caused by moisture.^[11] Reducing the overall weight of a sleeping bag by eliminating superfluous material will reduce its weight. 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 philosophy behind these two alternatives is that insulation crushed under a person's weight is devoid of air and therefore 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^[4] or an insulated jacket. Proper camping site selection that avoids colder hollows (low points where cold air tends to collect)^[4] 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, with a carrying limit of 25 pounds (11 kg).^[4] An internal-frame pack can weigh upwards of 6 pounds (2.7 kg) with features such as hip belt stabilizers, lifter straps, sternum straps, and compression straps; ultralight frameless packs are commercially available in weights ranging from eight to fourteen ounces (200-400 g)^[11] 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".^[4]

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.

Examples

Jardine:^[4]

• Backpack: homemade "ultralight pack" (13.5 ounces (380 g))
• Sleeping system: homemade polarguard 2-inch (5.1 cm) thick quilt (33 ounces (940 g)); stowbag (1.75 ounces (50 g)); trimmed ³⁄₈-inch (9.5 mm) thick, 36-inch (91 cm) long, closed cell polyethylene pad (4.8 ounces (140 g)); space blanket ground sheet (1.25 ounces (35 g))
• Rain shelter: homemade 9-foot (2.7 m) by 7-foot (2.1 m) silnylon tarp (12 ounces (340 g)); 8 aluminum tent stakes and stowbag (2.6 ounces (74 g)); guyline cord (0.5 ounces (14 g))
• Total: 69.4 ounces (1.97 kg; 4.34 lb)

Jordan:^[2]

• Backpack: commercial "ultralight pack" (3.7 ounces (100 g))
• Sleeping system: commercial 2.25-inch (5.7 cm) loft down sleeping bag (15.2 ounces (430 g)); spinnaker cloth stuff sack (.5 ounces (14 g)); torso sized, ³⁄₈-inch (9.5 mm) thick, sleeping pad (1.9 ounces (54 g));
• Rain shelter: commercial poncho-tarp made of spinnaker cloth 5-foot (1.5 m) by 8-foot (2.4 m) (6.3 ounces (180 g)); silnylon bivy sack (6.2 ounces (180 g)); 6 titanium tent stakes (1.3 ounces (37 g)); 24 feet (7.3 m) UHMWP guyline (0.2 ounces (5.7 g))
• Total: 35.3 ounces (1.00 kg; 2.21 lb)

Other gear

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 that some Ultralight hikers choose instead of traditional backpacking gear include:

• Making a fire instead of carrying a stove.
• Light weight alcohol stove such as a beverage can stove or solid fuel stoves instead of heavier gas stoves and a single cook pot ("billycan") with a single spoon instead of a traditional mess kit.
• Some ultralight hikers opt to not carry a stove and its associated paraphernalia at all, relying on no-cook meals for food.
• Trail running or running shoes (Grandma Gatewood used Keds sneakers) instead of hiking boots and lightweight nylon socks instead of heavy wool socks.
• The minimal amount of extra clothing safely possible.
• An ultralight hiker's first-aid kit and repair kit are often stored in plastic or silnylon bags instead of the conventional (and heavier) packaging that a traditional backpacker might carry. The contents can also be optimized, for example Jordan^[2] proposes a 5-ounce (140 g) kit.
• A 1 ounce (28 g) mini pocket knife instead of a heavier Leatherman style multi-tool or Swiss army knife.
• Chemical disinfectant water treatment (iodine tablets, chlorine dioxide) instead of heavier water filters. Some are known to carry no purification or filter and ingest untreated water straight from a wilderness source.^[12][13]
• Plastic Soft drink 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.

Consumables

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

In addition to carrying equipment, hikers must also carry consumables such as water and food and in some cases fuel. Some ultralight backpackers save weight by resupplying these items more frequently. On long-distance trails with multiple access points, some ultralight hikers choose to place food caches or stop at stores to resupply consumables at frequent intervals, allowing just two or three days' worth of food to be carried in place of a larger load.

Water

1 litre (1.1 US qt) of water weighs 1 kilogram (2.2 lb), thus it is a significant contributor to pack weight.

Moderate activity in a moderate climate requires 2 litres (2.1 US qt) of drinking water per day,^[14] and in many regions hikers must carry their water from oasis to oasis. 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 (or is smart enough to double back before becoming dehydrated).

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 heavier filters. Ultra Violet (UV) treatment devices are also used. These devices deactivate DNA in viruses, bacteria, and protozoa rendering them non-infectious, if present. The devices weigh about the same as filters, but being electronic, require batteries. Boiling, disinfectants, UV devices and/or ordinary filters are not effective against chemical pollution.^[4]

Food

A common variety of trail mix made out of peanuts, raisins, and candy coated chocolate, around 4.8 kcal/gram^[1]

Once the Big 3 and water are resolved, food becomes 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.^[14] 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.^[14] Thus depending upon type of food an average hiker carries, a hiker requires approximately 2 kilograms (4.4 lb) of food per day.^{[citation needed]} Ultralight techniques can substantially reduce this weight, Jardine suggests 2.5 pounds (1.1 kg) per day for thru-hiking,^[4] 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.^[2]

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 used for centuries by the 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,^[15] thus carrying foods high in fat content can reduce weight, such as:

• Peanut butter (5.89 kcal/gram^[14])
• Nuts (Pecans are 6.87 kcal/gram,^[14] toasted coconut is 5.92 kcal/gram^[16])
• Pemican (5.7 kcal/gram^[17])
• Dried whole egg (5.92 kcal/gram^[14])

Clarified butter (anhydrous), which stores well unrefrigerated, is almost pure fat (8.76 kcal/gram^[18]), thus about 4,000 kcal per pound; however, it is also a potent bear attractant.

Alternatively, so-called "energy bars" on average contain more protein and carbohydrates than fat, similar to a fig newton (3.68 kcal/gram), lowering their calorie to weight ratio relative to other choices.^[19]

Food protection

A captive bear tests a food canister

In many areas, unprotected food has the potential of being eaten by wild animals. In many areas, food is hung in trees to keep it away from ground animals, but this is ineffective where animals have become accustomed to humans. In the U.S.A.'s Yosemite National Park where there are numerous black bears, hanging food is ineffective, and an approved bear-resistant food storage container is required.^[20] The conflict with the ultralight hiker philosophy is that approved bear-proof containers^[21] are both bulky to pack and can weigh between 1 lb, 9 ounces (879 g)^[22] at the lightest, to 3 lbs, 2 ounces (1.42 kg)^[23] at the heaviest.

References