According to Men’s Total Fitness, rowing machines are not only great for aerobic workouts, but they also work all of your body's major muscle groups. What’s more, you don’t have to go to the gym to work out on a rowing machine, as many manufacturers make high-quality rowing machines -- and even rowing machines that fold up for easy storage -- that are suitable for home use. Two popular types of rowing machines are the water rower and the air rower.
However, I own an air rower and have zero worries about maxing out it’s ability. I can completely exhaust myself on any type of workout. Air and water rowers are the chosen resistance type by Olympic athletes and any athlete looking to train their full-body cardio. I don’t think they would choose this resistance type if they felt they could max it out.
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.