Disclosed is a rotational friction brake actuated and regulated by the rate of change of the angular speed, comprising: a first body, a second body rotationally attached to the first body, the second body being arranged to rotate around a rotational center axis of the second body, a actuator arrangement configured to move a second friction surface into frictional engagement with the first friction surface, the actuator arrangement comprising an actuator arm being pivotably attached to the second body in a pivot point, wherein the pivot point is eccentrically offset to the rotational center axis, the actuator arrangement having a radius of gyration being longer than a distance from the pivot point to the rotational center axis, wherein the actuator arrangement has an internal flexibility which allows a shape of the actuator arrangement to depend on centrifugal forces acting thereon. The disclosure further relates to a fishing reel comprising such a rotational friction brake.
