Breathing is unique among the various natural rhythms in the human body. It is a rhythm that is influenced by all the three parts of the brain - reptilian (that controls autonomous life sustaining mechanisms), limbic (that controls emotional functions) and neocortex (that controls voluntary functions). There are various breathing rhythms like inhalation, exhalation, and nostril dominance. These rhythms are affected by the physiological, emotional, and cognitive state of the person. Also, by voluntarily changing the various parameters and ratios of these rhythms, we can influence the physiological, emotional, and cognitive states. Traditional Indian texts on Yoga give several techniques to do these. Many of these have been studied in research settings. There is a lot of scope for more research in this area. Here we review the published literature on the research performed on the rhythm of breathing including some of the techniques from the traditional Yoga texts. We have identified several gaps in the research, methodology and inconclusive outcomes as well as highlighted the potential areas of greater scope of study.