Fastpackers enjoy the increased freedom of movement that comes with a light and fast approach. A lightweight backpack allows fastpackers to also use lighter footwear and maintain a faster pace, including the ability to use a running gait at times. This can make a big difference in overall efficiency and enjoyment. Fastpackers trade the comforts of a well equipped camping setup for the ability to see more terrain in less time, travel in more rugged terrain, and burden their muscles and joints with less load. Competitve Fastpacking is not a recognized athletic event but is usually included in longer adventure races. There are fastest known recorded times for popular trail and mountain routes that are continually challenged by elite Fastpackers and Mountain Runners, but the vast majority of this activity is done strictly for pleasure.
There are three styles of Fastpacking: supported, self-supported, and unsupported. Supported means there is a support team that can supply or tend to the Fastpacker along the way at various checkpoints along the route. These are generally the fastest, lightest trips, and they offer increased safety in case of an emergency. Self-supported trips do not involve a dedicated support team but they allow for self-caching of supplies in advance along the route, and using stores, lodgings, and/or other facilities along the way. Unsupported trips do not make use of outside assistance or self-caching of any supplies. Other than water and endemic edibles that can be ingested or collected along the way, all supplies are carried from start to finish. Unsupported, also known to mountaineers as “alpine style, ” is generally considered the least impactful and purest form of the sport. It is frowned upon for Fastpackers to beg supplies from other trail users, unless in an absolute emergency, and it is considered very important that Fastpackers, and all mountain travelers, adhere strictly to the seven ethical principles of Leave No Trace, and respect the laws of the land.
Lightweight & Ultralight Backpacking - These common terms are casually used interchangeably with Fastpacking, and with each other. They are all are virtually the same in terms of philosophy and approach, with subtle distinctions. Fastpacking confers a speed and distance component in addition to the lightweight aspects. Some lightweight backpackers simply want to lighten their load for comfort and enjoyment without desiring to move any faster, or over greater distances. The terms Lightweight and Ultralight have not been officially quantified but some have suggested that the term "lightweight" generally applies to backpackers with a 3-season base pack weight of less than 20 pounds and "ultralight" applies to less than 10 pounds. The terms "super-ultralight" and "extreme-ultralight" have emerged to apply to base weights less than 5 pounds and 3 pounds, respectively. These latter terms have not gained wide acceptance in the lightweight backpacking community, probably because their use takes focus away from the bigger picture philosophy and practical approach to planning and executing lighter backcountry trips, and instead puts emphasis on achieving specific base weight numbers.