When waves run into water moving in the opposite direction, they are slowed, just as if they were approaching a beach. Wave length becomes shorter, wave height higher, and they may break. A good (bad) example of this is an ebb current flowing out of Raccoon Strait into waves coming in from the Golden Gate. Good rough water training, if that’s what you want.
This type of machine provides a smooth action with little wear and tear to the mechanism, and the flywheel itself could help to keep you cool as you work out. It's worth noting that although water rowers aim for a realistic rowing feel, competitive rowers often use air rowers for land training. They tend to be less expensive than water-powered rowing machines, as well.
Open water rowing is an ALL-BODY SPORT, toning your arms, legs, chest, back, and abs. Rowing is also recognized as a COMPLETE CARDIOVASCULAR WORKOUT which is highly aerobic and burns calories quickly. What most people don't realize is that rowing IMPROVES JOINT HEALTH through a wide range of motion. In addition, open water rowing RELIEVES STRESS and allows you the opportunity to remove yourself from the world around you, to connect to the calm and quiet of the water, and to meditate through the rhythmic, repetitive motion of your stroke.
The rowing machine itself is unlike any other on the market with its patented water filled flywheel. It is hard to exactly copy the action of a scull on the water, but the mechanics of the flywheel spinning in water comes in a close second on dry land. The fact that the water is 800 times denser than air means that there is no need for any extra resistance or dampening that you will find in normal air rowers. The faster you pull, the more resistance is generated giving it infinite variability. However, if you want to be able to practice rowing with a faster stroke, you will have to reduce the amount of water in the tank unlike an air rower where you just have to adjust the baffle.