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What is Chronobiology?

By Melinda Perkins –   

Circadian Rhythm.   Biological Rhythm.    Body Clocks.

We’ve heard the words. We might use them in casual conversation. We might even preach to our clients the importance of them. But if put on the spot, would we be able to accurately and specifically define them? How about effectively adding them into a program or workup for our patients or clients?

All of those words and more stem from the overarching area of Chronobiology.

Would it surprise you to learn that you could supercharge your client’s results just by sprinkling in a bit of timing know-how?

Let’s take a look:

Chronobiology is a multidisciplinary field of study where scientists research the rhythms of living organisms. Oddly, prior to the last few decades, much of the work revolved around plants. Since it branched out to animals, and finally humans, our understanding of the effects of the physical, solar, lunar and environmental cycles has skyrocketed. 

Here’s the rundown.

As humans, we have a circadian master clock which runs on a 24 hour cycle based on light and dark information. This clock resets when sunlight hits the eye. That’s why blue light limitation has become so popular for maintaining our sleep cycles, and thus, our better health. 

So, we have this master clock which is a group of cells called the suprachiasmatic nucleus (SCN) housed in the hypothalamus of the brain. As it goes, when we name something the “master”, it usually follows that there are other pieces of the puzzle which are less masterful. This is no different with our body clocks

These “less-masterful” entities are called peripheral clocks and reside in every tissue in the body. They oversee things like insulin release, fat storage, energy production and body temperature. Many of them both receive as well as send messages back to the SCN. All of them interact with our behaviors and the environment around us such as food intake, physical movement and body temperature. Among other things, they wake us up, send us to sleep, make us grow, tell our bodies to recover, assist movement, and help us digest.

Why do we care?

Okay, we’re talking clocks, right? 

Lots of clocks. 

Imagine an entire shop filled with hundreds of clocks. When they tick along in sync with each other under the direction of the master clock, the shop is filled with a melodious tick-tock song. When one or two get behind, it’s distracting to the ear. Add in a few more and the cacophony will send you running out the door. 

In our bodies this chaos is called circadian desynchrony (CD). Obviously, this is not a desirable state of being in a body that strives for homeostasis, balance and harmony.

Let’s talk about you…

Whether you realize it or not, you probably use chronobiology every day. Think about any client you have. When they first walked through your door, you noticed many things in an instant including their age and what they were wearing.

Their age told you of their journey through the years. (Circannual rhythm.) 

Clothing (and a glance out the window) told you of the season. Both of these fall in the category of chronobiology called infradian rhythms which have a cycle of more than 24 hours (monthly biannually or yearly) 

You invite them to sit down and you discover a bit more. You might ask about their eating habits, energy levels and what kind of work and exercise they do. From those things you know their rhythms of digestion, hormone release, productivity/focus, and energy production.

These are a second aspect of chronobiology called Ultradian cycles or things that happen multiple times in a 24 hour period. 

And lastly you might ask about their sleep and wake cycles. These bring us back to that 24 hour circadian rhythm and the all-important master clock.

Here’s what you might be missing:

Still thinking of that client…

What might not be outwardly apparent is that most people on the planet since the invention of the lightbulb are desynchronized with their master clock due to artificial light. Add to that a few irregular meal times, some weird sleep patterns and even an air conditioner over their desk at work and their internal clock shop sounds like a 5th grade orchestra warming up. Not only does the noise make you want to run for the hills, desynchronization has been correlated to everything from metabolic disease to neurological disorders to cancer. 

What can you do about it?

Meet the givers of time: …light…food…exercise

Okay, we’ve established that timing is everything. We have the master clock that sets the rhythm based on light. Then we have our peripheral clocks that listen to the master clock, but they also take cues from our behavior; how we eat and exercise. 

Back to our clock shop.

The tissues involved in digestion (stomach, endocrine, gut, etc.) have an optimal operating rhythm that is in sync with the master clock. When an individual eats at those specific times, the digestive system is ready to work and everything is primed for performance. Digestion is super efficient, delivery of nutrients to tissues is optimal, energy production is peak.

The result is a bevy of clocks in sync which is a beautiful thing!

But say, we skip meals and have midnight snacks. Skipping meals tells the body a story of scarcity (not a great thing unless you want to pack on the pounds). Then, that doughnut at midnight sets off a series of events. Not only is the digestive system not primed for food, but the alarms go off and the tissues report back to the master clock that it’s daytime. The master clock, getting its information from the eye says, “Nope.”. Suddenly our clocks are out of sync. 

Same goes with exercise.

Studies show that if you exercise out of sync with your natural rhythm, it actually has adverse effects like increased insulin resistance, decreased focus and coordination leading to higher possibilities of injury and even delayed melatonin release.

But how do you line up those clocks?

Here’s where true personalization comes in:

As a health professional, you already recognize that every client is an individual with different histories, present habits and future goals. What the study of chronobiology adds is that each person is endowed with a unique set of rhythms.  Their clocks tick in a completely personal way. Therefore, synchrony creates a distinctive song in each body. 

What does this mean?

Every person has certain times in the day where they perform mental tasks better or are more ready to move or digest. Add to that the times of day when they most need to socialize or be in nature or rest and the possibilities for pinpointing the precise intervention for that specific person unfold. When you understand the chronobiology of a client, you get a glimpse into the timing of their hormone release. Then, you can synchronize specific activities with the correct hormone release for that task and BAM! Success is simple!

Let’s get specific:

Say your client’s cortisol peaks super fast in the morning and their body temp is up super quick after rising. Essentially, they are ready for action. If you recommend exercise, hard mental tasks and complex productivity steps early in the day, they will ride the wave of their hormones, thus working with their natural rhythms.

Another client’s melatonin sticks around a bit longer in the morning, pushing that cortisol peak later in the day. These things, along with a natural drop in insulin sensitivity and greater cardiovascular efficiency in the afternoon, prime them for a trip to the gym later in the day.

And this is just the beginning. There are as many configurations as there are hormones in the body and people who walk in the door of your practice. 

But the same caveat applies: 

When your program harnesses the power of clocks ticking in sync, your clients feel strong, strive toward their goals with ease, enjoy life more and stick to it. They excel…and all things improve.

A final note:

Our desire is to create the perfect plan for each client to achieve their desired results in the shortest amount of time possible with the least effort expended. That is true efficiency. Adding the chronobiological component into our already effective programs takes our client/practitioner success to the next level. And who doesn’t want to do that?


To learn how to apply precision methods and technology solutions to your service offering and effectively add chronobiology and more to your practice, check out our Level 1 Course for Health Professionals.



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