Biorhythms show how our Physical, Emotional and Intellectual energies move in Rhythm. The theory of Biorhythms holds we move in rhythmic undulations of change that begin at birth. Separate and coexisting Cycles then influence our energies with a clockwork of change. We have a Physical Cycle of 23 days, an Emotional Cycle of 28 days, and an Intellectual Cycle of 33 days. In each Cycle, half time is High and half the time is Low.


The 23-day Physical Cycle is High for 11½ days that bring us greater energy and strength. We may increase our activity and produce greater output when the Cycle is High. For 11½ days, our Physical energy lessens. This is when we should not take on new loads, rather, this is a good time to maintain previous levels and allow our bodies to rebuild.

The 28-day Emotional Cycle is High for 14 days to bring us more enthusiasm and spirit. During this time, we may be more idealistic and expressive. For 14 days thereafter, we are more prone to realism, reservation and reflection.

The 33-day Intellectual Cycle is High for 16½ days when we learn more, think more, are more attentive and prone to new ideas. In the 16½ days following we are more inward as we digest what we have learned and contemplate the past.

Crossover Days occur in all three Cycles. This is the day when Cycle switches from High to Low or from Low to High It is this critical day that we cross the midpoint meridian and mishaps can take place. On this day in the Physical Cycle, we might be more accident prone and miss a step. When the Emotional Cycle reaches this day, we may be susceptible to angry or upset. A Crossover day in the Intellectual Cycle has more subtle effects but we can be subject to mistaken judgement. The day that the Cycle crosses over in either direction is critical because the momentum is neither up or down. At this point we susceptible a crisis of sorts from transitional chaos. In Cycle harmonics, Highs and Lows are motions which exert themselves in pendulum-like waves. A Crossover presents a period of transition without trend-like motion. This leaves a brief period of vulnerability.

Because of their mathematical precision, Biorhythms can be calculated from one’s day of brith to track their Highs and Lows, and Crossovers. This allows us to see where we are and forecast for any time. This will help us to understand our ebb and flow of energies and to work with them. The dance of life that is all around us in within us as well which allows for an element of predictability.

History of Biorhythms



Records from as far back as the fourth century, BC show that Androsthenes, the scribe for Alexander the Great who recorded descriptions of his marches, documented movements in the leaves of the tamarind tree. The leaves opened in the day and closed at night in a diurnal ‘sleep’ pattern. French scientist and astronomer, Jean Jacques D´Ortous de Mairan, performed tests in 1729 that showed that leaf patterns of the heliotrope plant continued to open by day and close by night even when kept on total darkness, proving the existence of an internal biological rhythm.

Related Studies:


Circadian Rhythms (cycles lasting about a day) that were known to exists in plants were also observed in animals. Early in the 1900s, Karl von Frisch and Ingeborg Beling noticed that bees visited flowers at certain times of the day even when placed in a man-made feeding station where nectar and daylight were absent. This demonstrated the presence of endogenous biological rhythms (originating within). Auguste Forel also found accurate test results on the biological systems of bees in 1910 and his work added to the interest in circadian rhythms. Sutherland Simpson and J.J. Galbraith made significant observations in mammalian behavior in 1906 while altering the environmental light-dark cycle. Gustav Kramer and Klaus Hoffmann studied the internal clocks of migrating birds in the 1950s and Colin Pittendrigh demonstrated that their internal clocks remained fixed regardless of environment. Results in the study of many types of circadian Rhythms are now pervasive.

Classical Theory:


Two doctors simultaneously discovered the Physical Cycle and the Emotional Cycle between 1897 and 1902. They are Dr. Hermann Swoboda and Dr. Wilhelm Fliess, considered to be the ‘fathers of biorhythms theory.’ Both men came to very similar conclusions about Physical, Emotional and Intellectual Rhythms, and they did so independently, without knowing the work of the other. Both men wrote many groundbreaking papers, booklets and books on the subject.

Dr. Hermann Swoboda
Dr. Hermann Swoboda

Dr. Hermann Swoboda

was a Professor of Psychology at the University of Vienna who researched periodic variations in fevers and who found rhythmic changes in mood and health. By collecting data on reaction to pain, fever outbreaks, asthma, heart attacks tissue swelling, onsets of illness and recurring dreams, he concluded that we have a 23-day Physical Cycle and a 28-day Emotional Cycle that could be used to predict mood and energy levels. In a paper he published in 1900 he stated: Even if one could lead a life completely devoid of outside influence, life would nevertheless not be the same day after day. The best of health does not prevent man from feeling unwell at times, or less cheerful than he is normally. Swoboda also tied the cycles to the birth date. He produced two successful and distinguished books on the subject:

  • Die Perioden des menschlichen Organismus in ihrer psychologischen und biologischen Bedeutung
(The Periodicity of Human Life) in 1904.
  • Studien Zur Grundlegung Der Psychologie
(Basis of Psychology) in 1905
  • Die kritischen Tage des Menschen und ihre Berechnung mit dem Periodenschieber
(The critical days of humans and their computation with the period slidegate valve) in 1909
his renown instruction booklet that described the Critical Days of Man
  • Das Siebenjahr. Untersuchungen über die zeitliche Gesetzmäßigkeit des Menschenlebens

Band 1: Vererbung (= alles Erschienene)

(The Year of The Seven) in 1917, his most famous book which gave analysis on the tendency toward predictable and
rhythmic births from generation to generation within the same family and that major events in life, such as birth, illness,
heart attacks and death fall on periodic days and involve family relationships.
Dr. Swobooda also developed a slide rule device to predict when critical days in these Cycles would occur.
Dr. Wilhelm Fliess
Dr. Wilhelm Fliess

Dr. Wilhelm Fliess

was a nose and throat specialist researching occurrent illness and death in his patients who made groundbreaking discoveries and was elected president of the Germanie Academy of Sciences in 1910. His conclusions also confirmed the existence of the 23-day and the 28-day Cycles and he instroduced these works to his friend and colleague, Dr. Sigmund Freud. In his work he found that men are more influence by the 23-day Physical (masculine) Cycle and that women are more influenced by the 28-day Emotional (feminine) Cycle, but concluded that both genders carry both Cycles. He recorded births and deaths in family tree lines and found connections across generations led him to note how nature have given a ‘clock’ that is pervasive throughout the plants and animals. Fliess published findings in his book:

  • Das Jahr des Lebendigen. Erstes und zweites Tausend (The Couse of a Life) in 1918.
Lectures that Dr. Fliess presented at many medical and scientific meetings were published in three books books between 1909 and 1929 as:
  • Mom Leben und Mom Tod (Of Life and Death)
  • DasJahrim Lebendigen (The Year in the Living)
  • Zur Periodenlehre (The Theory of Periodicity) a collection of lectures.
Dr. Fliess also made note of a 98-day long-term rhythm that brings rhythmic changes to feminine inheritance and emotional sensitivity. He ultimately concluded that there is a connection between the Rhythms he found and evolution, the creation of organisms and in life itself.


University of Innsbruck
University of Innsbruck

Alfred Teltscher

was a Viennese engineer and mathematician at the University of Innsbruck who noticed that his students had good days and bad days that followed a 33-day pattern, hence the 33-day Cycle. In is his many tests of the scholastic performance of High School students in the 1920s he found periods in which a student could readily grasp and absorb new subjects with mental agility, and comparable periods in which a student’ capacity to think quickly and clearly was diminished.

Dr. Rexferd Hersey
Dr. Rexferd Hersey

Dr. Rexford Hersey & Dr. Michael John Bennett

conducted similar research between 1928 and 1932 and came to a similar conclusion independent of any knowledge of Teltsher’s work. Dr. Hersey was a psychologist working at the University of Pennsylvania with assistance from Dr. Bennett when they developed these supportive simultaneous findings.


George Thommen
by George Thommen

George Thommen

popularized Biorhythms with the publication of his book:

  • Is this your day?: How biorhythm helps you determine your life cycles
1964 (ASIN: B000RPD4HY)
1973 (ISBN-13: 978-0517007426)
1973 Rev. Ed. (ISBN-13: 978-0517505991)
1987 (ISBN-13: 978-5551592839).

Thommen was a Swiss-born American who discovered the earlier works of founding physicians. He introduced these theories to the United States with this book which contained all of the material from which subsequent authors would base their books as they met popular demand in the 1970s. Biorhythm calculators also came onto the market for people to instantly calculate their biorhythms for any given day.

Additional Cycles:

Subsequent research by various people has led to widely publicized theories for the existence of additional Biorhythms Cycles. This has led to universally held beliefs in a fourth, fifth and sixth Biorhythm, defined as:
  • 38-day (Intuition) Cycle
  • 43-day (Aesthetic) Cycle
  • 48-day (Self-Awareness) Cycle

Additional theories on this subject identify another Cycle such as:

  • 53-day (Spiritual) Cycle
Even more studies search for the existence of Biorhythm Cycles beyond these.


Mort Gale
Mort Gale

Mort Gale

evidently published the earliest documentation on the subject of additional Biorhythms with his precedent-setting book:

in 1978 (ISBN-13: 978-0446815550). In it he defined the 38-day Intuitive Cycle and identified it as the fourth Biorhythm as he “suggested an alternative plotting format, and offered an interpretation of biorhythms based on Jungian concepts of human functions.”

Note to readers: This author supports the findings of Mr. Gale and the belief in the 38-day Biorhythm. K. David Katzmire also theorized the existence of a fourth Biorhythm in the late 1970s, believing it to be 38-days in length, a conclusion he reached independent of any knowledge of the work of Mort Gale. However, it is Mort Gale who came up with the idea first and who published it in his book which paved the way for the rest of us. The independent discovery of Katzmire is mentioned only to support the theory.

Perhaps the underlying principles that we find in Biorhythms are to be found elsewhere on earth. As we look to the affairs of nations and to the affairs of the world, may we remember the axion, ‘As Above, So Below,’ The tides of time itself may indeed turn in Rhythm as for all things there is a season. To seek answers to things great and small we need only to look within ourselves, even for the turn of civilizations and the Kala-Rhythms in our lives. For more to the Physical, Emotional and Intellectual triadic energies in our Rhythms, Personality Archetypes, Nations, and World Community, see links at: Sacred Geometry / Triadic Energy.