Water rowers are great exercise machines for getting a good workout indoors. Take the Stamina Wave Water Rower for instance: it uses dynamic resistance to give you a more realistic workout. It has a chest strap to track your heart rate. This rower combines with muuv for audio coaching.
This rower has a molded, ergonomic seat, folding frame, and built-in wheels. It has a LCD monitor to track calories burned, pulse, time, stroke count, and total distance.