Rest, Repair, and Resilience: Understanding Your Body's Circadian Rhythms

In today's fast-paced world, over commitment, chronic stress and experiences of burnout are becoming all too common. Finding ways to enhance our resilience is crucial for maintaining health and well-being. One powerful approach lies in understanding and nurturing our circadian rhythms—our body's internal clock that regulates essential functions over roughly 24-hour cycles. Let's delve into how embracing these rhythms can significantly impact our lives.

What Are Circadian Rhythms?

Imagine your body as a finely tuned orchestra, with each instrument playing in harmony to a rhythm that keeps everything in sync. This symphony is orchestrated by your circadian rhythms, managed by a master clock in your brain; also known as suprachiasmatic nucleus. This clock coordinates with other internal clocks throughout your body, regulating crucial functions like behavioural, physiological and cellular processes.

Scientists have discovered that approximately half of our genes follow a 24-hour rhythm in their activity levels across various tissues (1,3). This rhythmic gene expression isn’t just a curiosity—it’s fundamental to how our bodies function optimally.

When our circadian rhythms are disrupted—whether due to irregular sleep patterns, chronic stress, shift work, or even chronic jet lag—it can wreak havoc on our health. Research has linked circadian disruption to a host of serious conditions, including sleep disorders, depression, diabetes, neurodegenerative diseases, obesity, and even cancer (2).

Nearly every aspect of our biology is governed by circadian rhythms. From the quality of our sleep and our cognitive performance to our body temperature, hormone levels, and even blood pressure—everything works in tandem with our internal clock (2,3). This intricate temporal dance helps us stay balanced and in harmony with our environment.

Why does this matter? Our bodies have evolved to function optimally when our internal rhythms align with the natural cycles of day and night. This alignment, or synchrony, ensures that our biological processes occur at the right time and in the right sequence. When we disrupt this synchrony, through late-night Netflix binges or irregular mealtimes, we interfere with our body’s ability to maintain health and well-being.

Here’s why getting quality sleep matters:

• Memory and Learning: Sleep enhances memory consolidation and improves cognitive functions like decision-making and concentration.
• Physical Health: It supports immune function, cardiovascular health, and the body's stress response.
• Mental Health: Adequate sleep is essential for maintaining mood stability and emotional resilience.
• Metabolic Health: Proper sleep helps regulate hormones involved in appetite and weight management.

Understanding Sleep Stages

When thinking about getting the sleep you need, it’s normal to focus on how many hours of sleep you get. While sleep duration is undoubtedly important, it’s not the only part of the equation.

There are four stages of sleep, one for rapid eye movement (REM) sleep and three that form non-REM (NREM) sleep. Sleep stages are important because they allow the brain and body to recuperate and develop. Failure to obtain enough of both deep sleep and REM sleep may explain some of the profound health consequences such as poor thinking ability, emotional instability and physical health such as weight, cardiovascular health and hormone issues.

The Role of Light and Dark:

Your circadian clock relies heavily on external cues, particularly light and darkness. Exposure to sunlight triggers wakefulness and sets your internal clock for the day, while darkness signals the onset of sleep and sets your internal clocks during sleep time.

Melatonin is the key hormone secreted by the pineal gland that signals the master clock (suprachiasmatic nucleus) to operate. Melatonin, also know as the sleepy hormone, relies on darkness to be secreted (5). Conversely, morning sun, daylight and blue light suppresses the production of Melatonin which then signals the master clock to activate the natural rhythms to optimize your body's performance throughout the day. Melatonin’s key actions are, circadian rhythm, bone growth, immune modulation, hormone regulation, neuroprotection, antioxidant and sleep promotion. It is used widely as a therapeutic medication for many conditions (6).

Irregular routines and inappropriate light exposure particular at night over time will disrupt this delicate balance leading to fatigue and other symptoms of burnout.

Blue Light and Your Health: What You Need to Know

In our modern world, we're surrounded by artificial light—whether it's from our digital screens or indoor lighting. Unlike the natural red and orange hues of sunrise and sunset, artificial light, especially the blue light emitted by LEDs in digital devices, can disrupt our natural rhythms (7,8).

Studies show that exposure to blue light from smartphones, tablets, and TVs can confuse our circadian rhythm (7,8). Essentially, using these devices in the morning can trick our bodies into thinking it's midday, while nighttime use suppresses melatonin, the hormone that helps regulate sleep. This disruption not only affects our ability to rest but also impacts our overall health, mood, and cognitive function.

Interestingly, children are even more sensitive to blue light than adults, making it crucial to limit their screen time after sunset to avoid disrupting their sleep patterns.
Managing exposure to blue light, whether from digital devices or indoor lighting, is key to supporting our body's natural rhythms and promoting better sleep and overall health (9).

Time-Restricted Feeding: Aligning Eating with Circadian Rhythms

Just as your sleep is governed by your circadian clock, so too is your metabolism. Time-restricted feeding (TRF), a form of intermittent fasting, aligns eating patterns with your body's natural rhythms (11,12). By restricting eating to a specific window, typically earlier in the day and less than 12 hrs you can optimize metabolic processes and experience better health outcomes. However, the sweet spot is a 10 hour eating window most days and nailing that first meal with protein, complex carbohydrates.

I find people are keen to commit to intermittent fasting, however, misunderstand the importance of fasting at night and not in the morning particularly is you are experience metabolic health issues and are living a life with undue stress.

Studies show that early TRF can improve weight management, glycaemic control, and hormone balance. It underscores the importance of not just what we eat, but when we eat it, respecting our body’s biological rhythms for optimal function (11,12).

Hormones – Our internal Communicator

I love hormones, they are our communicators that like to tap us on the shoulder to let us know if something isn’t right. Particularly when life is getting tricky and you find yourself in habits such as going to be too late, eating odd hours, craving carbs or stimulants and sleeping in because you are so tired.

Unfortunately, after a while hormones and other metabolites start to play havoc on our health and can results in myriad unwanted symptoms, such as insulin resistance, pain, fatigue, allergies, autoimmune and anxiety. Cortisol is the hormone that is released by the adrenal gland and responds to stress, stimulants and late nights. The adrenal gland relies on consistent rest and repair for it to function optimally and to assist in reducing the cascade of unwanted health issues (15,16).

We cant always change the stresses in our life, but we can change the habits that support adrenal function.

Practical Steps for Building Resilience and Supporting the Circadian Rhythms

Enhancing resilience during times of chronic stress involves understanding and respecting your body's circadian rhythms. By prioritizing rest, quality sleep, and aligning daily routines with natural biological processes, you can optimize your health and well-being. Start small, make gradual changes, and observe the positive impact on your energy levels, mood, and overall resilience. Your body will thank you for it!

Remember, resilience isn't just about bouncing back; it's about thriving despite challenges—a journey best supported by honouring the rhythms that keep us balanced and healthy. As you embark on this journey, embrace the wisdom of your body's internal clock—it's the key to enduring vitality and well-being in a hectic world.

Actionable Steps:

• Prioritize Sleep Hygiene
  
• Embrace Time-Restricted Feeding
  
• Reduce Stressors
  
• Practice Mindfulness
  
• Manage Light Exposure
  
• Create a Sleep-Conducive Environment
  
• Establish a Routine
  
• Minimize EMF Exposure
  

I share more about some of these actionable steps in our new Rest & Repair Webinar that you can get instant access to now. Click below to get your hands on it and start getting better sleep!

Access Rest & Repair Webinar

References

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2. Samanta S, Ali SA. Impact of circadian clock dysfunction on human health. Explor Neurosci. 2022;1:4-30. https://doi.org/10.37349/en.2022.00002
3. Dose B, Yalçin M, Dries SPM and Relógio A (2023) TimeTeller for timing health: The potential of circadian medicine to improve performance, prevent disease and optimize treatment. Front. Digit. Health 5:1157654. doi: 10.3389/fdgth.2023.1157654
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8. Figueiro, M. G. and Rea, M. S. (2010) ‘The effects of red and blue lights on circadian variations in cortisol, alpha amylase, and melatonin.’, International journal of endocrinology. Hindawi Limited, 2010, p. 829351. doi: 10.1155/2010/829351.
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