Just like an ocean, life has rhythmic tides. Over various time periods, our body and mind fluctuates. These biological rhythms – biorhythms are controlled by our “internal clocks” and include long and short cycles:

  • Annual cycles – Typical annual cycles influence most animals and plant life. Cycles influence the migration of birds. Some animals, such as bears, hibernate. Humans may experience seasonal variations in appetite, sleep patterns and moods. Some people, especially in northern climates, experience depression during dark winter months. This is called a seasonal affective disorder.
  • 28-day cycles – Often called the lunar cycle, the female menstrual cycle, averages 28 days. Does this cycle cause fluctuating moods? Many believe it does but some psychologists are skeptical.
  • 24-hour cycles – Humans experience 24-hour cycles of varying alertness, body temperature and growth hormone secretions. Not only humans but all mammals and birds require sleep (Siegel, 2002). Even dolphins sleep with half their brain awake while the other half sleeps.
  • 90-minute cycles – Sleep cycles vary in 90-minute intervals. Smaller mammals have shorter sleep cycles (rats 9 minutes, cats and dogs 25 minutes) while large animals have longer sleep cycles (elephants 100 minutes or more) (Hobson, 1989).
  • 7-year cycles – Some researchers and psychologists believe humans have about 10 cycles throughout our lives, others believe humans have longer life-cycles of seven years.

This report is not a diagnosis. We hope this information can guide you toward improving your life.

Review our Knowledge Base or the links displayed on this page for similar and related topics.