Cycling eliminates these inefficiencies. The body remains largely stationary, and energy is transferred into motion through circular pedaling and rolling contact between tire and ground. Unlike walking, where each footfall involves braking followed by re-acceleration, a bicycle maintains momentum with minimal energy loss.<\/p>\n
![\"Cycling,group,training,on,a,road,bicycles,during,the,day\"](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2025\/11\/a-group-of-cyclists-riding-in-the-mountains.jpg\"\/)
Credit: Shutterstock<\/p>\n
According to a 1973 article in Scientific American<\/a>, later updated in 2025 for the magazine\u2019s 180th anniversary, a human on a bicycle expends just 0.15 kilocalories per kilogram per kilometer, while walking costs between 0.3 to 0.5 kcal\/kg\/km. This places the cyclist at <\/a>the top of the energy-efficiency <\/a>chart\u2014outranking birds, fish, and other high-performance movers in the animal kingdom.<\/p>\n The analysis shows that wheels\u2014arguably the simplest of all machines\u2014enable humans to coast similarly to gliding fish or birds, minimizing the energy typically lost to repeated muscular action or gravity. The rigid bicycle frame also supports the rider\u2019s weight, removing the need to expend muscular energy on balance or lift.<\/p>\n Muscle Mechanics and Metabolic Performance<\/p>\n Efficiency isn\u2019t just about motion\u2014it\u2019s also about how muscles work. Human muscle tissue is most efficient when operating under steady, low-speed contractions. As contraction speed increases, energy consumption rises disproportionately, a phenomenon known as the force-velocity relationship.<\/p>\n In walking or running, muscle contractions are fast and irregular. In cycling, they\u2019re consistent and adjustable. Gearing systems enable riders to maintain optimal muscle speeds even on varied terrain. As Blazevich writes, gears help keep muscles in their \u201csweet spot\u201d for energy and force output.<\/p>\n