Wikipedia
A rowbike is an example of a rowing cycle, hybrid fitness/transport machine that combines a bicycle, and a rowing machine. "Rowbike" is a trademark of the Rowbike company. The Rowbike was invented by Scott Olson, the creator of Rollerblade inline skates. "Rowling" is a combination of rowing and rolling and is sometimes used in place of rowing when describing a rowbike.
A rowbike is different from a bicycle in that a bicycle is powered by pedals utilizing the rider's legs, yet a Rowbike is powered utilizing the rowlers legs, back, core and arms as they engage in the back and forth, rowing motion. Rowbikes are marketed to people who desire a zero impact, total body exercise which is provided by rowing. The Rowbike works nearly every muscle in the rowler's body - as well as their mind.
Although a rowbike could be classified as a human powered vehicle, as opposed to a fitness machine, rowbikes are used in the United States almost exclusively for exercise and fitness, rather than for transportation. European rowlers often use Rowbikes for commuting to work. Four wheel variants also exist, and like most bicycles, rowbikes can be used with a stand that permits use as a stationary bike or indoor rower.