The advantages with air rowers is that there is smooth action; there is only small wear and tear to its mechanism; its automatic feature adjusts according to your rate of strokes; and there is a wide range of the resistance readily available in replicating the feel of rowing through the waters. The only disadvantage of this machine is that it tends to be noise indoors.
If you're looking at a WaterRower, you're probably also considering the Concept2. They're both great machines, but which you choose depends on your needs. I think the WaterRower is ideal for most people, but not everyone. The WaterRower has a number of advantages vs the Concept 2 - it is quieter, the mechanism up front is lower profile, it has a comfortable seat, it is much better looking, it's easier to stand up when you're not rowing and it's just ... zen-like. There is something about the smoothness of the WaterRower that makes it a joy to use, and because it's quiet you can easily stream your favorite binge-series without cranking the volume too high.
Heavyweight rowers of both sexes tend to be very tall, broad-shouldered, have long arms and legs as well as tremendous cardiovascular capacity and low body fat ratios. Olympic or International level heavyweight male oarsmen are typically anywhere between 190 cm and 206 cm (6'3" to 6'9") tall with most being around 198 cm (6'6") and weighing approximately 102 kg (225 lb) with about 6 to 7% body fat.
There are many differing sets of rules governing racing, and these are generally defined by the governing body of the sport in a particular country—e.g., British Rowing in England and Wales, Rowing Australia in Australia, and USRowing in the United States. In international competitions, the rules are set out by the world governing body, the Fédération Internationale des Sociétés d'Aviron (FISA). The rules are mostly similar but do vary; for example, British Rowing requires coxswains to wear buoyancy aids at all times, whereas FISA rules do not.
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.