Although some rowing machines are made of space-age, super-sweat-resistant metals, you still want to wipe off the equipment after a sweaty workout.  These machines are usually constructed with a lot of various materials and salty sweat can be very corrosive.  Keeping your rowing machine clean can go a long way toward extending its life, and its appearance.
Rowing is unusual in the demands it places on competitors. The standard world championship race distance of 2,000 metres is long enough to have a large endurance element, but short enough (typically 5.5 to 7.5 minutes) to feel like a sprint. This means that rowers have some of the highest power outputs of athletes in any sport.[35] At the same time the motion involved in the sport compresses the rowers' lungs, limiting the amount of oxygen available to them. This requires rowers to tailor their breathing to the stroke, typically inhaling and exhaling twice per stroke, unlike most other sports such as cycling where competitors can breathe freely.

For a third option, you can look to hydraulic machines, which use pistons to generate resistance. Hydraulic rowers are quiet, and they also tend to be smaller and cheaper than other kinds of rowing machines, but you won’t get the same smooth rowing feel, or the consistency of resistance, that you would get with an air or water rower. What's more, reviewer after reviewer has found them unreliable and high-maintenance.
Each machine has been hand finished with Danish Oil and Urethane for protection. Wood has been chosen due to its marvelous engineering properties, primary amongst these is its ability to absorb sound and vibration enhancing the WaterRower's quietness and smoothness of use. Ash, like all woods used in WaterRower construction, is a premium hardwood with incredible longevity and dimensional stability. For reasons of ecology, all our woods are harvested from replenishable forests. 

Water rowers feature a tank that is actually filled with water as a means for resistance. As you increase the pace of rowing, the resistance naturally increases as well. This means that you can set your own pace and resistance in a single motion. The same is true for air rowers. Air rowers use a fan or flywheel to create resistance, and you have control over the intensity of the workout due to the fact that the air resistance depends on your pace. Most water and air rowers come equipped with -- or at least have as an option -- monitors that track various functions such as distance, strokes, strokes per minute and calories burned.

The tank of the WaterRower Oxbridge Rower is made from polycarbonate, one of the strongest plastics available. It is virtually indestructible. The tank is sealed and can be filled with municipal water via a small opening closed by a stopper. This water typically contains enough chlorine to remain clear for some time. After exposure to light, the chlorine will degrade; the chlorine tablets should be added periodically.
The first known "modern" rowing races began from competition among the professional watermen in the United Kingdom that provided ferry and taxi service on the River Thames in London. Prizes for wager races were often offered by the London Guilds and Livery Companies or wealthy owners of riverside houses.[10] The oldest surviving such race, Doggett's Coat and Badge was first contested in 1715 and is still held annually from London Bridge to Chelsea.[12] During the 19th century these races were to become numerous and popular, attracting large crowds. Prize matches amongst professionals similarly became popular on other rivers throughout Great Britain in the 19th century, notably on the Tyne. In America, the earliest known race dates back to 1756 in New York, when a pettiauger defeated a Cape Cod whaleboat in a race.[13]
In sweep or sweep-oar rowing, each rower has one oar, held with both hands. This is generally done in pairs, fours, and eights. In some regions of the world, each rower in a sweep boat is referred to either as port or starboard, depending on which side of the boat the rower's oar extends to. In other regions, the port side is referred to as stroke side, and the starboard side as bow side; this applies even if the stroke oarsman is rowing on bow side and/or the bow oarsman on stroke side.