Abstract: A gymnastic bicycle includes a frame mountable on the floor and having at a forward portion a tubular part or stem which supports a handlebar and at a rear portion a tubular part supporting a seat and provided with a pedal shaft operable by pedals. Incorporated in an articulation zone between the lower end of the tubular piece or stem supporting the handlebar and the frame of the bicycle is a friction device having an adjustable resistance which permits the physical force of the user to be adjusted when he practices an exercise corresponding to rowing, such exercise taking place by the forward and backward oscillation of the handlebar. At such articulation zone is a main vibrating mechanism whose main operating element is a polygonal member securely mounted on the pedal shaft so that the vibrations produced as a result of the operation of the main vibrating mechanism are transmitted to the handlebar of the bicycle.