1. An apparatus for controlling a threshold for detecting peaks of physiological signals, the apparatus comprising: electrodes configured to electrically contract a user to be examined to measure a physiological signal from the user to be examined; a memory configured to store the physiological signal and a detection threshold; and a processor configured to: obtain the physiological signal, determine whether the physiological signal exceeds the detection threshold which, when exceeded, indicates a peak of the physiological signal has been detected, update, in response to the processor determining the physiological signal exceeds the detection threshold, the detection threshold by calculating a difference between a predetermined minimum threshold value of the detection threshold and a feature value of the detected peak and a difference between a previous detection threshold and the feature value of the detected peak, and update, in response to the processor determining the physiological signal does not exceed the detection threshold, the detection threshold by calculating a difference between the predetermined minimum threshold value of the detection threshold and the detection threshold and a difference between the previous detection threshold and the detection threshold, wherein the processor is further configured to control a speed, at which the updated detection threshold is reduced, according to the calculated difference and a weight adjusted based on a user environment, and wherein the previous detection threshold was updated to obtain the detection threshold.