Systems and methods for sonification, user influence through sound, and biofeedback, sonification of motion and physiological parameters during physical exercise and the use of music and sound in order to influence the emotional, psychological and physiological state of an exerciser, and the use of sonification and influence in a feedback loop to create a particular exercise experience for a user. A digital music player comprises physiological sensors, a controller, a user interface, a music decoder, a music playback modulator, and an audio data store. The user interface allows a user to specify target values for the physiological sensors as a function of time, the controller selects a playlist of audio data based on the target values, the music decoder decodes the audio data in a sequence corresponding to the playlist, and the music playback modulator causes the sequence and/or the decoding to be modified according to the values of the physiological sensor.