Questions & Answers

What Are the Primary Biorhythm Cycles?

Short Answer

Biorhythms are typically divided into 3 primary cycles and 3 secondary cycles. The 3 primary cycles are the physical, emotional and intellectual cycles. These primary cycles measure 23 days, 28 days and 33 days respectively.

Biorhythms measure our energy levels, which rise and fall throughout the weeks and months of our lives. These energy levels can be divided into 3 primary energy cycles and 3 secondary energy cycles. The 3 primary cycles are our physical cycle, our emotional cycle and our intellectual cycle.

As their names suggest, these primary cycles affect different aspects of our lives. Each cycle rises and falls according to its own unique rhythm. Each primary biorhythm cycle starts on the day we are born, and each cycle continues independently until the day we die.

How long is each primary cycle?

Each of our 3 primary biorhythm cycles repeats after a specific number of days:

Physical Biorhythm Cycle: Repeats every 23 Days
Emotional Biorhythm Cycle: Repeats every 28 Days
Intellectual Biorhythm Cycle: Repeats every 33 Days

This means, for example, that we reach our peak physical performance every 23 days, but we’re also at our worst physical performance about half way through the cycle after that — or about 11.5 days after each peak.

There are 23 days total in the physical biorhythm cycle

Likewise, we are at our “emotional best” every 28 days, and we’re at our emotional worst, about 14 days after each peak.

emotional biorhythm example

Our primary intellectual cycles are the longest and slowest. We achieve our peak mental performance every 33 days, and we’re all at our least sharp, or mentally slowest about 16.5 days after each intellectual peak.

intellectual biorhythm example

So why are they called “primary cycles” and not just “biorhythm cycles”?

Most biorhythm readings are divided into two parts. The first part of a biorhythm reading consists of the 3 primary cycles discussed above. The second part of a biorhythm reading consists of 3 secondary cycles.

These secondary cycles aren’t true biorhythm cycles, but instead are composites or averages of the first three cycles. Secondary cycles are often considered less important, but they’re also more specific. They can help to understand the relationships between our primary cycles, and how they interact with each other.