The Cambridge Challenge Adjustable Resistance Rower makes ingenious use of the unique physical properties of water. Just as a wave can be anything from a gentle ripple to a raging ocean surf, so the Cambridge Challenge A/R Rower instantly adapts from a light warm-up to a fierce Workout, by adjusting the resistance level. That's because with water, the harder you exercise, the tougher it gets. Ask any rower! Cambridge Challenge A/R Rower has been developed in collaboration with professional rowers to deliver the feel, sight and sound of real on-water rowing. The multiple chamber, ribbed tank internals provide natural 'catch' at the start of the stroke, and the most smooth and consistent resistance you will find on any rowing ergometer. The water level is easily varied through the adjustable resistance system to change the overall resistance profile to perfectly suit every user.