A biorhythm is a cyclical pattern of biological activity that begins at birth. There are three sine wave cycles controlling our Physical, Emotional and Intellectual highs and lows.

Physical
The physical cycle has a period of 23 days and controls our energy, vitality, stamina, vigour, endurance and initiative. When our physical cycle is up, we are more likely to feel better, be full of energy, and less likely to become ill. When our physical cycle is down, we tend to tire more easily and are more prone to catch colds and other illnesses.

Emotional
The emotional cycle has a period of 28 days and controls our sensitivity and temperament. When our emotional cycle is up, we are more likely to be cheerful, creative, artistic and sensuous. When this cycle is down, we are more likely to be moody, bad tempered, irritable and depressed.

Intellectual
TThis cycle has a period of 33 days. When it is up we think quickly, solve problems effectively, do well on tests and retain facts to memory. When it is down, we display poor memory and judgement. We may find it hard to concentrate. Poor decisions may be made during this period.

Critical or Zero Days
The magnitude of the cycles has no significance except to indicate negative, zero and positive values. Days in which a curve crosses the centre line are known as critical days. On these days, your system may be in turmoil. Things are likely to go wrong and you may be more accident prone.