The objective of the proposed study is to examine the effects of various breathing patterns on heart rate variability. Heart rate variability (HRV) is the variation of the interbeat intervals or the time between one heart beat and the next, in milliseconds. HRV is considered to be an adaptive function and has been shown to serve as a quantifiable indicator of autonomic balance and homeostatic control. A breathing pattern is the within-cycle respiratory time or the ratio between the inspiration and expiration of breath, including the pause time at the top of the inspiration and at the bottom of the expiration. Very little research has been done to research the effects of breathing patterns on HRV- despite the fact that past examinations do suggest that the within-cycle respiratory times of breath do affect autonomic activity. This study intends to reveal the most effective breathing pattern in relation to one's psychophysiological state.