Simply put, it is the best low-impact, full-body workout available! The full body rhythmic nature of rowing makes it wonderfully efficient at burning calories while also developing flexibility and strength. Rowing is impact-free and the intensity is completely user-controlled. The advanced design of the XTERRA Fitness ERG500 air turbine converts wind power into resistance to closely simulate the action of rowing. The conveniently located lever adjustment features 8 resistance levels that regulate the airflow out of the air turbine. This allows you quickly and easily control your resistance during your workout.