A pseudoscience that purports the theory that human behavior is characterized by regular, predictable body rhythms that begin at the moment of birth.
A regular process of change which takes place within living organisms, e.g. sleeping, waking or the reproductive cycle.
Supposed regular pattern of changes in a person’s energy level, responsiveness, and attitude, as determined by genetic, physiologic, or other internal individual factors, or by external factors such as atmospheric pressure, ion content of the air, or amount of stress accumulated.
Natural physical cycles. Examples of biorhythms include the sleep-wake cycle and the reproductive cycle. Biorhythms are thought by some people to affect behavior and mood physically, emotionally, and intellectually. According to this view, biorhythms can help explain why people have good days and bad days.
A cyclic phenomenon (e.g., circadian rhythm, sleep cycle, and menstrual cycle) that occurs with established regularity in living organisms.
Part of a theory that suggests that human life is strongly affected by three biological cycles. The idea of such cycles developed in stages. Their existence was first proposed by the German Wilhelm fliess, a contemporary of Sigmund freud. He proposed two such cycles, and an Austrian engineer named Alfred Telscher suggested a third. Herman Swoboda then added to their idea the observation that the cycles began at birth. By tying them to the birth date, any person’s present relationship to his or her cycles could be quickly and easily calculated. Although the idea of biorhythms existed since the turn of the century, it only became popular in the 1970s. By that time several instruments had been developed to calculate quickly and interpret individual biorhythm charts.
The biorhythm chart tracks the course of a 23-day cycle of physical strength; a 28-day cycle of emotional sensibility, intuition, and creative ability; and a 33-day cycle of mental activity, reasoning, and ambition. The chart indicated when people are at their best in any of the cycles. Practitioners believe that individuals are especially strong when two or three cycles reach their peak at approximately the same time.
The term “circadian rhythm” is employed to describe physiological functions that exhibit rhythmic variations. One example is the menstrual cycle, which occurs approximately every 28 days in fertile women. Circadian rhythms refer to recurring patterns that follow a roughly 24-hour cycle and play a significant role in regulating various bodily processes and behaviors.
Most biorhythms are rooted in a daily or circadian (24-hour) cycle. Our bodies are governed by an internal clock, which is regulated by hormones released into the bloodstream by endocrine glands. The levels of sleepiness and wakefulness experienced can be influenced by the secretion of melatonin, a hormone released by the pineal gland in the brain. Melatonin production is stimulated by darkness and inhibited by light. Another hormone, cortisol, produced by the adrenal glands, also fluctuates in accordance with the sleep-wake cycle, with lower levels in the evening and higher levels in the morning.
When air travel across distant time zones disrupts the usual division between night and day, it causes a disturbance to the body’s internal clock, resulting in a phenomenon known as jet lag.