Human physiology is the study of how the human body functions. It encompasses molecular, cellular, endocrine, cardiovascular, respiratory, and other physiological systems. Applied human physiology includes areas like space physiology, sports physiology, exercise physiology, and clinical physiology. The field is becoming more holistic as it appreciates interactions within the body and between the body and its internal and external environments, both currently and historically. In the future, human physiology may also study the interrelationships between human consciousness and the natural world, applying this wisdom to individual and social life. Ancient medical disciplines and traditional wisdom may contribute insights to this evolving understanding.