Cycling
Cycling is the activity of propelling a bicycle—a human-powered, two-wheeled vehicle—for transportation, recreation, or competitive purposes.[1] The bicycle's development began with Karl von Drais's 1817 invention of a steerable wooden "swiftwalker," evolving through pedal-driven models in the 1860s to the chain-driven safety bicycle in the 1880s, which enabled widespread adoption due to its stability and efficiency.[2] First organized races emerged in 1868, laying the foundation for professional cycling.[3] Today, cycling supports daily commuting in urban areas, with countries like the Netherlands reporting over 50% of residents using bikes regularly for transport, contributing to reduced emissions and traffic congestion.[4] Empirical studies link regular cycling to enhanced cardiorespiratory fitness, lower risks of cardiovascular disease and cancer, and a 10% reduction in all-cause mortality compared to non-cyclists.[5][6] In elite competition, the Tour de France stands as cycling's premier endurance event, demanding riders cover over 3,500 kilometers in three weeks across varied terrain.[7] However, the sport's history includes systemic doping, with substances like amphetamines used since the early 20th century and epitomized by Lance Armstrong's 2012 confession of blood doping during his seven consecutive Tour victories from 1999 to 2005, resulting in stripped titles and eroded trust in results.[8][9] Despite anti-doping reforms, retrospective analyses reveal high conviction rates among Tour participants, underscoring ongoing challenges to integrity. The global bicycle industry, valued at over $60 billion annually, reflects cycling's economic scale amid growing emphasis on its role in public health and sustainable mobility.