The biorhythms theory asserts that human life is affected by rhythmic biological cycles and attempts to determine
the period when a person is susceptible to get the best performance in executing a particular task or, on the contrary, to determine the days when special care should be taken or certain tasks or actions should be
avoided to prevent potential accidents.
Although people have always been aware that periods favorable for accidents and failures seem to alternate with
periods in which nearly everything seems to succeed, these cycles have only been the subject of scientific research since the end of the 19th century, in particular by W. Fleiss, H. Swoboda, A. Teltscher and R. Hersey.
The fluctuations of our biorhythms can explain our varying moods and why sometimes we "feel good" or
"feel bad" without apparent cause.
Though many rhythmic cycles govern our biological processes and our lives the classic (or Primary) biorhythms that
control human behavior are the 23-day Physical, the 28-day Emotional and the 33-day Intellectual (or Mental) cycles.
These cycles start at the time of birth and continue to oscillate between a maximum (100 %) and a minimum (-100 %)
until the end of life. This means that at the time of birth the three primary biorhythms are at the crossover point (0 %) between positive and negative phases of the cycles. This state is only reached again after
about 58 years and two months (23 x 28 x 33 = 21252 days).
The days on which a cycle crosses the midline, moving from the positive phase to the negative phase or from the
negative phase to the positive phase, are considered "Critical days". This transition does not happen suddenly but gradually. It is generally assumed that the transition from a "normal" state to
a critical day (or vice versa) begins about 12 hours before the hour of birth and that the critical day ends about 12 hours after the hour of birth. This means that a critical day can in fact start the previous day
or last part of the next day. Critical days are days when extra caution should be exercised because on these days our reactions to the environment could potentially develop a critical situation. During the above
mentioned time frame of about 58 years and two months (21252 days), 20.4 % of the days are critical days.
The 23-day Physical cycle
relates to physical stamina, endurance, energy, resistance, physical confidence, physical condition.
The 28-day Emotional cycle
relates to creativity, feelings, reaction time, love, cooperation, temperament, emotion, sensitivity.
The 33-day Intellectual cycle
relates to clear thinking, memory, mental ability and responses, analytical ability, creative thinking.
Although the three Primary biorhythms were the first to be recognized and are considered the most important,
additional rhythms have been discovered. These Secondary biorhythms are:
Intuitional cycle: 38 days: unconscious perception, instinctive decisions, paranormal activity.
: 43 days: creativity and imagination, interest in the beautiful and the harmonious.
Awareness cycle: 48 days: confidence and self-awareness, ability to percieve own personality and
Spiritual cycle: 53 days: inner stability and relaxed attitude.
Still more cycles are sometimes mentioned. These Additional (or Extra) cycles result from the combination (average)
of two primary cycles and are:
Mastery cycle: results from the combination of Physical and Intellectual cycles.
: combination of Intellectual and Emotional cycles.
Passion cycle: interaction of Physical and Emotional cycles.
always keep in mind that biorhythms are obviously part of a much larger complex of influences. They are not horoscopes and they never
hold a prediction of the future but, in their regularity, offer the possibility to accurately calculate a person's disposition and use that knowledge to that person's advantage.
The theory of biorhythms is the object of many criticisms and its plausibility is contested by some. Consequently,
the biorhythm calculator software proposed on this site is to be used for entertainment only and should not be considered a scientific application.