About recumbent bikes
A recumbent bicycle is a bicycle that places the rider in a laid-back reclining position. Most recumbent riders choose this type of design for ergonomic reasons; the rider’s weight is distributed comfortably over a larger area, supported by back and buttocks. On a traditional upright bicycle, the body weight rests entirely on a small portion of the sitting bones, the feet, and the hands.
Most recumbent models also have an aerodynamic advantage; the reclined, legs-forward position of the rider’s body presents a smaller frontal profile. A recumbent holds the world speed record for a bicycle, and they were banned from racing under the UCI in 1934 and now race under the banner of the Human Powered Vehicle Association (HPVA).
Recumbents are available in a wide range of configurations, including: long to short wheelbase; large, small, or a mix of wheel sizes; overseat, underseat, or no-hands steering; and rear wheel or front wheel drive. A variant with three wheels is a recumbent trike.
Advantages of recumbent compared to erect bicycles:
Advocates cite a number of advantages over traditional upright bicycles, although some of these advantages, such as reduced wrist or neck pain, are only in comparison to sport or racing bicycles with their forward-leaning riding position, not city bikes with their erect riding position.
Safety. Particularly with the lower designs, the recumbent bicycle’s low center of mass and short distance from the ground significantly reduce the consequences of a fall for the rider. In particular, the recumbent cyclist’s head is roughly half a meter (and in some cases, as much as 1 meter) lower than that of a conventional cyclist. The worries of head injuries (including both standard compression-type concussions and axial-rotational-type brain damage) are therefore reduced. A direction-of-travel fall from a recumbent will be less harmful than from an upright bike due to the feet-first orientation, which ensures that the rider cannot be pitched headfirst over the handlebars.
Additionally, the low center of mass greatly increases braking and stopping capabilities, since the recumbent design avoids the concern of vigorous front-wheel braking resulting in the rider flying over the handlebars. This may, however, increase the risk of a front wheel skid. Likewise, losing a front wheel or fracturing a front fork will also be far less injurious than in a conventional bike. Furthermore, the recumbent design makes it possible to cycle very close to the curb without risking a pedal-curb collision.
Comfort. The recumbent riding position reduces strain on the body, making it particularly suitable for long rides and touring.Depending on the angle of the seat, it can be very easy on the neck,wrists, hands, arms, shoulders, lower back, and ischial tuberosities (“sit bones”). Riders who suffer back pain or genito-urinary trouble often find that recumbents allow them to make significant rides without pain. Urogenital trouble is less because the pedals are not under the seat, thus the seat can be larger so weight can be distributed to a larger area and to the seat back. Shorts made for recumbent riders do not have padding or any need for it.
Obese comfort. An obese person on an upright bike must lean forward, allowing his stomach to flop forward to be compressed with each leg-lift. The recumbent riding position will allow the excess body mass to be spread across allowing the rider to exercise comfortably.
View angle. The recumbent riding position, if not too aggressively reclined, can enable the rider to face straight ahead comfortably and view the passing scenery. Many upright bikes, particularly those used incompetition, on the other hand, have a riding position in which the natural position is to face more downwards towards the pavement; in order to face straight ahead, the neck must be craned upward.
Health. Many riders switch to recumbents to alleviate the chronic back or neck pain from riding upright bikes. On trikes, the inherent stability of three wheels allows very low gearing to be used, so hills can be climbed without strain on joints. Also, on some recumbents, the rider’s legs are nearly at the same height as the heart. This reduces the rider’s hydrostatic pressure, thus allowing venous blood to more easily return to the heart. This physiological effect of improved circulation suggests an increase in rider endurance and/or increased power output on long rides. Recumbent riders are not bent over as are conventional bike riders, and this makes breathing easier. Additionally, studies indicate that upright bicycle riding may be a cause of male impotence due to pressure placed on the perineal nerve by the seat recumbent seats do not present the same issue.
Speed. On declines, on the flat, or on shallow inclines, the more horizontal recumbent bicycle designs are generally faster than upright bicycles for the same level of effort because the aerodynamic profile of the rider reduces wind resistance. It is this feature which led to the Union Cycliste Internationale (UCI) banning them in the 1930s . The world speed record for human-powered vehicles was set by Dutch cyclist Sebastiaan Bowier pedaled a streamliner (a fully faired recumbent) for 200 m (660 ft) at 133.78 km/h (83.13 mph) in the Velox3 at Battle Mountain, Nevada.
Turns. Rider can continue pedaling even during tight turns without the pedals striking the ground although recumbents have larger turning circles than most conventional bicycles.