In the Paleolithic or ‘hunter gatherer’ era, from 2.6 million years ago until the agricultural revolution 10,000 years ago, our ancestors woke up with the rising sun in the morning and rested for a good nights sleep not long after sundown. Scientists estimate that our Paleolithic ancestors averaged about 10 hours of sleep per night. Of course the absence of an external light source, television sets, and laptops made it a little easier to get to bed so early, but the benefits are deeply engrained in our DNA.
Your circadian rhythms are based on the light and dark cycles of the day and have a profound effect on your bodyweight, cardiovascular health, fertility, and well-being. Melatonin, your body’s sleep hormone, is secreted in the evening about 3 hours after your last meal. It makes you feel tired, drowsy, and prepares you for deep rejuvenating sleep.
In winter, Paleolithic people slept longer hours – approximately 10-12hrs per night – as the days got shorter and darker. Your immune and hormonal functions are linked to these evolutionary circadian rhythms of light and dark, and understanding how this effects you will help you improve your energy levels, build muscle, burn fat, and upgrade your overall health.
For example, daylight increases your dopamine and cortisol output, getting you out of bed and ready for the day ahead. When was the last time you felt energized in the morning? How many cups of coffee do you go through to get yourself going in the morning? Do you need your alarm clock to wake up or do you wake up naturally?
Your natural hormonal patterns shift throughout the day and by nightfall your cortisol and dopamine levels should be at their lowest, allowing melatonin production to kick in and stimulate your repair and rejuvenation hormone... growth hormone. Growth hormone is essential for rebuilding your body while you sleep, helping to build lean muscle, burn fat and keep your immune system strong. (Your body is hard at work while you rest!)
So what’s the problem with our 21st century sleep patterns?
Two generations ago, our grandparents average about 9-10 hours sleep per night, not very far off our Paleolithic ancestors. Today, the average North American gets between 6-7.5 hours of sleep, about an hour or two less than the recommended 8 to 8.5 hours sleep per night. Over the course of a year, this would amount to approximately a 500-hour ‘sleep debt’!
Over-consuming coffee can add to the problem. How do you know if you are over-doing the stimulants?
You’ve been abusing your coffee intake if you don't feel the same ‘kick’ from your morning cup of joe, or if stopping your intake results in headaches, irritability, or intense fatigue. Coffee triggers the production of adrenaline from the adrenal glands and stimulates our sympathetic – ‘fight or flight’ – nervous system. While this is okay in moderation, chronically relying on this form of energy is like revving the RPM’s on your car constantly into the red zone. Before too long, you'll burn out your engine!
So what can you do to start cutting into your sleep debt?
Let’s start in the bedroom. The key to sleep is ensuring you have total darkness in your bedroom. Make sure to remove all light sources (think red lights from the alarm clocks), cell phones on the bedside table, and nearby laptops from the vicinity of your head. All of these stimulate the nervous system and prevent deep sleep. Next, turn off the television or shut off your laptop at least an hour before bed to allow your body to unwind. All of these stimulants activate the nervous system and prevent deep sleep. Finally, get to bed before midnight to increase your number of sleep hours per night. In Tradtional Chinese Medicine (TCM), every hour of sleep before midnight counts as DOUBLE, because they are so valuable for restoring health and wellness.
Make time to 'schedule' in more sleep... it will pay off with better energy, productivity, and performance at work and in the gym!
Dr Marc Bubbs ND, CISSN, CSCS
Check out more articles in the SLEEP SERIES...
- 7 (Evidence-Based) Reasons To Nap More
- Ancestral Clues To Better Sleep
- After Hours Emails Ruining Your Sleep?
- How Important Is Sleep? Just Ask The World Series Champs!
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