If you’re interested in using a rowing machine for focused training — whether for outdoor rowing, an indoor competition, or as part of a larger fitness program — you’ll want air resistance. If you’re drawn to rowers for the enjoyability (alongside the full-body, cardio-plus-strength training efficacy) of a rowing workout, consider a machine with water resistance.
If the machine is to be housed on a wooden floor you will need a mat beneath to reduce vibration and also noise. If space is tight, the hydraulic options are usually the smallest. It's also worth checking your floor can take the weight if you're going for one of the bigger, heavier models. For most, this shouldn't be a problem, if you have any doubts get a surveyor to check as it could be a very expensive mistake!
The WaterRower Natural is outfitted with a Series 4 performance monitor that's designed to balance technical sophistication with user-friendliness. The monitor--which includes six information and programming windows, six QuickSelection buttons, and three navigation buttons--displays your workout intensity, stroke rate, heart rate, zone bar, duration, and distance. Plus, the monitor is compatible with an optional heart rate chest strap and receiver, which helps you optimize your workout and achieve your exercise objectives.