An indoor rowing machine is a form of aerobic fitness equipment that resembles the range of ... motion that rowing on water produces. This machine is most commonly used for rowing training and aerobic exercise training. Rowing machines come equipped with ergometers which are devices that measure the amount of work performed or force produced by the athlete. Indoor rowers also measure the amount of energy or calories the athlete expends while exercising with this equipment. Indoor Rowers are suitable for both home gym and commercial gym use.