A method and device is described, which measures and records one or more repetitive biological signals, such as heartbeat, breathing rate, and/or intrinsic brainwave frequency, and uses these tempos and timing information as a feedback mechanism to an individual doing one or more repetitive motion activities, in order to synchronize the activities with the repetitive biological signals, or a simple ratio of harmonics or sub-harmonics thereof. The feedback is achieved through a visual, audio, or tactile signal that indicates to the individual pacing information for precisely when to perform the activity. The purpose of synchronizing repetitive motion activity to biological activity is to optimize the efficiency of the system as a whole, reducing energy consumption and promoting calm and focused performance. Repetitive motion activities include but are not limited to breathing, running, bicycling, swimming, walking, hiking, jump rope, and rowing.
