According to the Varibike company, a study conducted by the University of New Mexico indicated that a rider’s maximum power output could be increased by over 30 percent when using both their arms and legs, as opposed to only their legs. Of course, using all four limbs would also provide a more complete work-out.
Along with the arm cranks, the Varibike also has a set of quite narrow flat handlebars. Riders can switch to them in situations where they want a little more stability, or just feel like changing to a more upright position. Additionally, the shifter and brake levers are located on them.
Steering looks like it could be a little ... unusual, but is reportedly achieved simply by leaning one's body into the turns.
Source: gizmag.comAdded: 26 August 2013