"In the nineteenth century, studies first began on certain life rhythms or cycles that were later termed "biorhythms". The word biorhythm is a compound of two Greek words, bios and rhythmos, which mean life and a constant or periodic beat. The theory of biorhythms defines and measures three basic and important life cycles in man: the physical, emotional, and intellectual." More here.

MedicineNet.com about Biorhythms

Biorhythm Calculator Name Birth data Day 12345678910111213141516171819202122232425262728293031 Month JanFebMarAprMayJunJulAugSepOctNovDec Year 20242023202220212020201920182017201620152014201320122011201020092008200720062005200420032002200120001999199819971996199519941993199219911990198919881987198619851984198319821981198019791978197719761975197419731972197119701969196819671966196519641963196219611960195919581957195619551954195319521951195019491948194719461945194419431942194119401939193819371936193519341933193219311930192919281927192619251924192319221921192019191918191719161915191419131912191119101909190819071906190519041903190219011900 Hour * 000102030405060708091011121314151617181920212223 Min * 000102030405060708091011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859 Your UTC time zone * 12 : Wellington (NZ), Fiji, Marshall Islands11 : 10 : Australia9 : 8 : 7 : 6 : 5 : 4 : Abu Dhabi, Muscat, Tblisi, Volgograd, Kabul3 : Kuwait, Nairobi, Riyadh, Moscow2 : Athens, Helsinki, Istanbul, Jerusalem, Harare1 : Copenhagen, Brussels, Madrid, Rome, Oslo0 : London, Dublin, Lisbon, Reykjavik-1 : Azores-2 : -3 : Brasilia, Buenos Aires-4 : Caracas, La Paz-5 : Bogota, Lima, New York-6 : Mexico City, Saskatchewan-7 : -8 : Los Angeles-9 : -10 : -11 : -12 : * Less important Primary rhythms Physical Emotional Intellectual Secondary rhythms Spiritual Awareness Aesthetic Intuition Biorhythm Report