Cycling, also known as bicycling or biking, is the activity of riding a bicycle or other types of pedal-driven human-powered vehicles such as balance bikes, unicycles, tricycles, and quadricycles. Cycling is practised around the world for purposes including transport, recreation, exercise, and competitive sport.

History

Cycling became popularized in Europe and North America in the latter part and especially the last decade of the 19th century. Today, over 50 percent of the human population knows how to ride a bike.SIBILSKI, LESZEK J. "Cycling Is Everyone's Business" , The World Bank, 2 April 2015

War

The bicycle has been used as a method of reconnaissance as well as transporting soldiers and supplies to combat zones. In this it has taken over many of the functions of horses in warfare. In the Second Boer War, both sides used bicycles for scouting. In World War I, France, Germany, Australia and New Zealand used bicycles to move troops. In its 1937 invasion of China, Japan employed some 50,000 bicycle troops, and similar forces were instrumental in Japan's march or "roll" through Malaya in World War II. Germany used bicycles again in World War II, while the British employed airborne "Cycle-commandos" with folding bikes.

In the Vietnam War, communist forces used bicycles extensively as cargo carriers along the Ho Chi Minh Trail.

The last country known to maintain a regiment of bicycle troops was Switzerland, which disbanded its last unit in 2003.

Equipment

In many countries, the most commonly used vehicle for road transport is a utility bicycle. These have frames with relaxed geometry, protecting the rider from shocks of the road and easing steering at low speeds. Utility bicycles tend to be equipped with accessories such as mudguards, pannier racks and lights, which extend their usefulness on a daily basis. Since the bicycle is so effective as a means of transportation, various companies have developed methods of carrying anything from the weekly shop to children on bicycles. Certain countries rely heavily on bicycles and their culture has developed around the bicycle as a primary form of transport. In Europe, Denmark and the Netherlands have the most bicycles per capita and most often use bicycles for everyday transport.

Road bikes tend to have a more upright shape and a shorter wheelbase, which make the bike more mobile but harder to ride slowly. The design, coupled with low or dropped handlebars, requires the rider to bend forward more, making use of stronger muscles (particularly the gluteus maximus) and reducing air resistance at high speed.

Road bikes are designed for speed and efficiency on paved roads. They are characterized by their lightweight frames, skinny tires, drop handlebars, and narrow saddles. Road bikes are ideal for racing, long-distance riding, and fitness training.

Other common types of bikes include gravel bikes, designed for use on gravel roads or trails, but with the ability to ride well on pavement; mountain bikes, which are designed for more rugged, undulating terrain; and e-bikes, which provide some level of motorized assist for the rider. There are additional variations of bikes and types of biking as well.

The price of a new bicycle can range from US$50 to more than US$20,000 (the highest priced bike in the world is the custom Madone by Damien Hirst, sold at US$500,000), depending on quality, type and weight (the most exotic road bicycles can weigh as little as 3.2 kg (7 lb)). However, UCI regulations stipulate a legal race bike cannot weigh less than 6.8 kg (14.99 lbs). Being measured for a bike and taking it for a test ride are recommended before buying.

The drivetrain components of the bike should also be considered. A middle-grade derailleur is sufficient for a beginner, although many utility bikes are equipped with hub gears. If the rider plans a significant amount of hillclimbing, a triple-chainring crankset gear system may be preferred. Otherwise, the relatively lighter, simpler, and less expensive double chainring is preferred, even on high-end race bikes. Much simpler fixed-wheel bikes are also available.

Many road bikes, along with mountain bikes, include clipless pedals to which special shoes attach via a cleat, enabling the rider to pull on the pedals as well as push. Other possible accessories for the bicycle include front and rear lights, bells or horns, child carrying seats, cycling computers with GPS, locks, bar tape, fenders (mud-guards), baggage racks, baggage carriers and pannier bags, water bottles and bottle cages.

For basic maintenance and repairs cyclists can carry a pump (or a CO2 cartridge), a puncture repair kit, a spare inner tube, and tire levers and a set of allen keys. Cycling can be more efficient and comfortable with special shoes, gloves, and shorts. In wet weather, riding can be more tolerable with waterproof clothes, such as cape, jacket, trousers (pants) and overshoes and high-visibility clothing is advisable to reduce the risk from motor vehicle users.

Items legally required in some jurisdictions, or voluntarily adopted for safety reasons, include bicycle helmets, generator or battery operated lights, reflectors, and audible signalling devices such as a bell or horn. Extras include studded tires and a bicycle computer.

Bikes can also be heavily customized, with different seat designs and handle bars, for example. Gears can also be customized to better suit the rider's strength in relation to the terrain.

Mode choice Whether to cycle or use other modes of transportation relate to many factors influencing the mode choice decision for each trip. These include cycling infrastructure including surface, urban road space allocation and parking, perceived traffic safety, weather and climate, personal fitness, motivation and situation, route type including length and steepness, and the physical performance of the vehicle(s) available.

In favorable conditions, such as a medium-distance trip in pleasant weather and surroundings on a good surface that is flat or slightly downhill, probably most healthy people who can cycle and have a bicycle or similar available will use it, because the motive power required to travel at a comfortable speed is very small and not felt, due to the relatively low weight, low rolling resistance - of sufficiently inflated tires - and high mechanical efficiency of even basic bicycles. Yet acceleration from a low to a slightly higher speed is almost instantaneous and because of air resistance any desired level of exertion can be reached, or reduced at will. The comfortable level of exertion is higher than for most other physical activities because of the very effective convective cooling of the body by the air flow from the forward motion.

As soon as any of these listed factors become less favorable, motivation to cycle reduces, but can be increased again, for example with more specialized bicycles or suitable clothing.

Skills Many schools and police departments run educational programs to instruct children in bicycle handling skills, especially to introduce them to the rules of the road as they apply to cyclists. In some countries these may be known as bicycle rodeos, or operated as schemes such as Bikeability in the UK. Education for adult cyclists is available from organizations such as the League of American Bicyclists.

Beyond simply riding, another skill is riding efficiently and safely in traffic. One popular approach to riding in motor vehicle traffic is vehicular cycling, occupying road space as car does. Alternately, in countries such as Denmark and the Netherlands, where cycling is popular, cyclists are often segregated into bike lanes at the side of, or more often separate from, main highways and roads. Many primary schools participate in the national road test in which children individually complete a circuit on roads near the school while being observed by testers.

Infrastructure

Cyclists, pedestrians and motorists make different demands on road design which may lead to conflicts. Some jurisdictions give priority to motorized traffic, for example setting up one-way street systems, free-right turns, high capacity roundabouts, and slip roads. Others share priority with cyclists so as to encourage more cycling by applying varying combinations of traffic calming measures to limit the impact of motorized transport, and by building bike lanes, bike paths and cycle tracks. The provision of cycling infrastructure varies widely between cities and countries, particularly since cycling for transportation almost entirely occurs in public streets. And, the development of computer vision and street view imagery has provided significant potential to assess infrastructure for cyclists.

In jurisdictions where motor vehicles were given priority, cycling has tended to decline while in jurisdictions where cycling infrastructure was built, cycling rates have remained steady or increased. Occasionally, extreme measures against cycling may occur. In Shanghai, where bicycles were once the dominant mode of transport, bicycle travel on a few city roads was banned temporarily in December 2003.

In areas in which cycling is popular and encouraged, cycle-parking facilities using bicycle stands, lockable mini-garages, and patrolled cycle parks are used to reduce theft. Local governments promote cycling by permitting bicycles to be carried on public transport or by providing external attachment devices on public transport vehicles. Conversely, an absence of secure cycle-parking is a recurring complaint by cyclists from cities with low modal share of cycling.

Extensive cycling infrastructure may be found in some cities. Such dedicated paths in some cities often have to be shared with in-line skaters, scooters, skateboarders, and pedestrians. Dedicated cycling infrastructure is treated differently in the law of every jurisdiction, including the question of liability of users in a collision. There is also some debate about the safety of the various types of separated facilities.

Bicycles are considered a sustainable mode of transport, especially suited for urban use and relatively shorter distances when used for transport (compared to recreation). Case studies and good practices (from European cities and some worldwide examples) that promote and stimulate this kind of functional cycling in cities can be found at Eltis, Europe's portal for local transport.

A number of cities, including Paris, London and Barcelona, now have successful bike hire schemes designed to help people cycle in the city. Typically these feature utilitarian city bikes which lock into docking stations, released on payment for set time periods. Costs vary from city to city. In London, initial hire access costs £2 per day. The first 30 minutes of each trip is free, with £2 for each additional 30 minutes until the bicycle is returned.

In the Netherlands, many roads have one or two separate cycleways alongside them, or cycle lanes marked on the road. On roads where adjacent bike paths or cycle tracks exist, the use of these facilities is compulsory, and cycling on the main carriageway is not permitted. Some 35,000 km of cycle-track has been physically segregated from motor traffic, Factsheet The Netherlands: cycling country — CBS equal to a quarter of the country's entire 140,000 km road network. A quarter of all trips in the country are made on bicycles, one quarter of them to work. Even the prime minister goes to work by bicycle, when weather permits. This saves the lives of 6,000 citizens per year, prolongs life expectancy by 6 months, saves the country 20 million dollars per year, and prevents 150 grams of from being emitted per kilometer of cycling.

Types

Utility

Utility cycling refers both to cycling as a mode of daily commuting transport as well as the use of a bicycle in a commercial activity, mainly to transport goods, mostly accomplished in an urban environment.