An assistance control system adapted to facilitate operation of a cycle, the cycle including a cycle body, and an assistance module that is controlled to output an assistive torque for driving movement of the cycle body, the cycle body including two pedals, two brake-levers, a bottom bracket spindle, and a crankset that is co-rotatably coupled to the bottom bracket spindle, the pedals being rotatably mounted to the crankset, one of the bottom bracket spindle and the crankset being driven to rotate by the assistance module with the assistive torque, said one of the bottom bracket spindle and the crankset being rotatable in a forward direction for propelling the cycle to move forward, and in a backward direction that is reverse to the forward direction, said assistance control system including: a first sensor mountable on the cycle body, and configured to sense operation of the cycle body so as to output a first sense signal indicative of a state of usage of the cycle body; and a controller communicable with said first sensor and the assistance module, and configured to, based on the first sense signal, switch between a boost mode where said controller outputs a control signal to said assistance module so as to control said assistance module to increase the assistive torque, and a deboost mode where said controller outputs the control signal to said assistance module so as to control said assistance module to decrease the assistive torque, wherein said first sensor is to be mounted on one of the bottom bracket spindle and the crankset, and is configured to sense movement of said one of the bottom bracket spindle and the crankset, wherein the first sense signal indicates a state of movement of said one of the bottom bracket spindle and the crankset, and wherein said controller is configured to switch to one of the boost mode and the deboost mode when it is determined based on the first sense signal that a rotation direction of said one of the bottom bracket spindle and the crankset has been repeatedly transitioned between the forward direction and the backward direction for a predefined number of times within a predefined sense period, said assistance control system being characterized by: a second sensor mountable on one of the brake-levers, and communicable with said controller, said second sensor being configured to sense operation of said one of the brake-levers and to output a second sense signal based on result of the sensing, the second sense signal indicating that said one of the brake-levers is in a pull condition; wherein said controller is configured to output the control signal to said assistance module after receiving at least one of the first sense signal and the second sense signal, and to switch to, based on the second sense signal, an awaken mode where said controller outputs the control signal to control said assistance module to be powered on. a first sensor mountable on the cycle body, and configured to sense operation of the cycle body so as to output a first sense signal indicative of a state of usage of the cycle body; and a controller communicable with said first sensor and the assistance module, and configured to, based on the first sense signal, switch between a boost mode where said controller outputs a control signal to said assistance module so as to control said assistance module to increase the assistive torque, and a deboost mode where said controller outputs the control signal to said assistance module so as to control said assistance module to decrease the assistive torque, wherein said first sensor is to be mounted on one of the bottom bracket spindle and the crankset, and is configured to sense movement of said one of the bottom bracket spindle and the crankset, wherein the first sense signal indicates a state of movement of said one of the bottom bracket spindle and the crankset, and wherein said controller is configured to switch to one of the boost mode and the deboost mode when it is determined based on the first sense signal that a rotation direction of said one of the bottom bracket spindle and the crankset has been repeatedly transitioned between the forward direction and the backward direction for a predefined number of times within a predefined sense period, said assistance control system being characterized by: a second sensor mountable on one of the brake-levers, and communicable with said controller, said second sensor being configured to sense operation of said one of the brake-levers and to output a second sense signal based on result of the sensing, the second sense signal indicating that said one of the brake-levers is in a pull condition; wherein said controller is configured to output the control signal to said assistance module after receiving at least one of the first sense signal and the second sense signal, and to switch to, based on the second sense signal, an awaken mode where said controller outputs the control signal to control said assistance module to be powered on. a second sensor mountable on one of the brake-levers, and communicable with said controller, said second sensor being configured to sense operation of said one of the brake-levers and to output a second sense signal based on result of the sensing, the second sense signal indicating that said one of the brake-levers is in a pull condition; wherein said controller is configured to output the control signal to said assistance module after receiving at least one of the first sense signal and the second sense signal, and to switch to, based on the second sense signal, an awaken mode where said controller outputs the control signal to control said assistance module to be powered on.