A handling machine comprising: a main body, a telescoping handling arm mounted on said main body and rotatable about a horizontal axis of rotation, and deployable and retractable along a longitudinal direction of said handling arm, actuators configured to raise and lower and deploy and retract said handling arm; a tilt detector configured to produce a signal relative to a tilting moment applied to the main body about a tilting axis of said handling machine; movement detectors or movement request detectors configured to produce a signal relative to movements or movement requests of the handling arm relative to the main body; and a control unit configured to receive the signals from the tilt detector and from the movement detectors or movement request detectors and to: slow, prevent or stop the movement of the handling arm if the signal representative of the tilting moment is greater than an effective threshold; assign a value to said effective threshold in response to a determination of a movement or of a movement request to lower the handling arm; characterized in that said value is a value of a lowering threshold and that the control unit is configured to: assign a value of an extension threshold to said effective threshold in response to an explicit or implicit determination of a movement or of a movement request for extension of the handling arm; and wherein the value of the lowering threshold is less than the value of the extension threshold. a main body, a telescoping handling arm mounted on said main body and rotatable about a horizontal axis of rotation, and deployable and retractable along a longitudinal direction of said handling arm, actuators configured to raise and lower and deploy and retract said handling arm; a tilt detector configured to produce a signal relative to a tilting moment applied to the main body about a tilting axis of said handling machine; movement detectors or movement request detectors configured to produce a signal relative to movements or movement requests of the handling arm relative to the main body; and a control unit configured to receive the signals from the tilt detector and from the movement detectors or movement request detectors and to: slow, prevent or stop the movement of the handling arm if the signal representative of the tilting moment is greater than an effective threshold; assign a value to said effective threshold in response to a determination of a movement or of a movement request to lower the handling arm; slow, prevent or stop the movement of the handling arm if the signal representative of the tilting moment is greater than an effective threshold; assign a value to said effective threshold in response to a determination of a movement or of a movement request to lower the handling arm; characterized in that said value is a value of a lowering threshold and that the control unit is configured to: assign a value of an extension threshold to said effective threshold in response to an explicit or implicit determination of a movement or of a movement request for extension of the handling arm; and wherein the value of the lowering threshold is less than the value of the extension threshold. assign a value of an extension threshold to said effective threshold in response to an explicit or implicit determination of a movement or of a movement request for extension of the handling arm; and wherein the value of the lowering threshold is less than the value of the extension threshold.