The water flywheel is comprised of two paddles encased in an enclosed tank of water. As you pull the cable, the paddles move through the water creating resistance. The beauty of this machine is it uses the mass/density of water. The paddles create the drag, so the harder you pull, the more resistance increases. Think about moving your hands through water. The faster you go, the more dense water feels. The slower you go, the less you feel the resistance. And this type of resistance is excellent for your joints. Click here to read the full review.
One downside of the Waterrower for me are the footrests. Whilst they are perfectly adequate if you want to row in shoes, rowing barefoot, which is something I like to do, is impossible. The plastic is completely square at the bottom and has sharp edges that cut into your heels. I also found that my shoes get caught when trying to put them in and out of the holders, which is a bit irritating.
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.
There is some minor maintenance. Because it's made out of wood, which can expand and contract, the bolts need tightening every few months or so. It's easy and takes only a couple of minutes. That, and putting in a fresh water purification tablet every six to twelve months, are about it for regular maintenance. The only problem I've had with the rower (the reason for 4 stars instead of 5) was a squeak that developed after about 6 weeks. It took me some time to determine the source of the squeak, which was a metal bracket connecting the footrest board to the horizontal boards above the drum. I had to partially disassemble the top section and tighten four bolts, but that fixed the problem and it's been quiet ever since.
Noise level is another large factor that tips the scale more towards water rowers. Air rowers make a fairly loud “whooshing” noise every stroke, which makes them bad for people who like watching TV, have sleeping children, live in apartments, or like working out early in the AM. Water rowers do make some noise but the splashing of water in the tank is a lot quieter and more soothing than the fan noise produced by air rowers.
The WaterRower Natural is handcrafted in solid ash and stained honey oak for consistency of color. The wood was chosen due to its marvelous engineering properties, especially its ability to absorb sound and vibration, which enhances the WaterRower's quiet performance and smooth operation. Ash, like all woods used in the construction of the WaterRower, is a premium hardwood with incredible longevity and dimensional stability. In addition, the wood is harvested from replenishable forests and is hand finished with Danish oil to provide a deep luster.