The Science of Sleep

By Janet Bertrand

Sleep, oh what a concept. If only we all had 8 glorious hours to spend in deep slumber, waking up refreshed and ready for a new day! Our bodies rely on rest, and not just rest but deep uninterrupted sleep. Sleep is the time when your body heals itself, when muscles repair and when a chorus of bodily functions occurs playing out like a well orchestrated symphony.

When we sleep our bodies go into a restorative mod, slowing our breathing and heart rate, creating a shift from day time functions to night time. When and how you sleep is as or more important than how much you sleep. Yes it’s fine to take a nap here and there but, overall getting good nights sleep is optimal. I am often asked how the lack of sleep really affects someone. I want to say it is not the lack of sleep but the lack of “quality sleep” that is important.

When we sleep certain hormones are released. One, being melatonin which is a natural occurring hormone that is released when we are asleep and it is dark. The minute light penetrates our eyes weather it be the sun or a light bulb, melatonin release will stop. Melatonin acts as an antioxidant and is secreted only when it is dark. There is some evidence that supports the belief that tumor development is influenced by a lack of melatonin. It is critical therefore to make sure we turn off all lights when sleeping and try to follow as closely as we can the natural cycle of day and night.

That cycle of one 24 hour period can be described as a Circadian rhythm. Those rhythmus determine when certain bodily functions take place. There is timing in the way our bodies function in a 24 hour period. Think of it as stages that our body passes through, each important as the next, like a passing of the baton, and yes there are consciousness to dropping that baton.

When the light enters our eyes and we rise for the day, the photoreceptors that are located in our retinas create messages to the Suprachiasmatic nucleus (SCN). There are a number of things that are affected at this point, including and not limited to, temperature, hormones, and metabolism.  Cortisol as well is somewhat lower at night and then surges in the early morning. What is interesting is some of the bodies organs do not have direct access to sunlight yet they function differently when they follow the peripheral clocks of that of a night shift worker who wakes up in unnatural light. Many biological and cellular processes are controlled by the peripheral clock and they affect the time keeping genes that are present in organs all over our body. For the body to function at peak or even efficient capacity it is important that all these things are in sync with each other. The SCN is like a coach and the peripheral clocks are like athletes who need to follow their direction with maximum activity during specific times of the day to get optimal performance from the body.

Another issue to look at is lack of sleep which can affect the body in a number of damaging ways. One being the under production of leptin which suppresses appetite and the over production of ghrelin, which is a hormone that promotes hunger.  When people are not well rested there is an over production of ghrelin. Our brains then send messages to eat foods that are high in sugar and starches. So it is almost like our bodies are trying to stay awake by artificial means but also playing havoc with our waistlines!!!

One other problem with lack of sleep that is of importance to us in the fitness world is the affect on performance. An athlete relies on their mind as much as their muscles when playing a game. It is important that internal circadian time and sleep time are adequately lined up for optimal cognitive benefit. When we are in the game we want to make sure we have all engines firing and using every natural means to our advantage. Keeping your eyes on the ball and mind on the finish line can be the difference between getting good solid nights sleep and maintaining on just a few hours.

According to Diplomat American Board of Sleep Medicine and one of Fitness Quest 10’s very own clients, Mindy Cetel, new studies are currently discovering new consequences of not enough sleep. “One recent study found that when an adult slept less than 6 hours a night there was a rise in inflammation in the body. When the same subject slept longer (ex: on the weekend) there inflammation receded. The problem is in the prolonged state of inflammation during the week, when people are trying to cheat sleep and get away with very little. There is still not clear evidence that says what this will do over say, a 20 year period.
 
When asked what we can do to get a better nights rest Cetel had some great advice: 
 
Falling asleep
Everyone should have wind down time. This should be right before you actually go lie down and fall asleep. All showers, grooming, whatever should be done and all that’s left is lying down. Activates would include reading something light, watching something pleasant and “fluffy” on TV or soft music. No computer because it is stimulating and interactive. 
 
Going back to sleep (interrupted sleep)
If you do happen to wake up in the middle of the night and begin to obsessed about how many hours you have left to sleep, you start something Cetel calls the “Busy Brain”. “It is best to turn the clock around, so you can’t see it at all”. You can set an alarm, but when you look at the clock and start the count down till morning, it can be almost impossible at that point to get back to sleep. You want to take a mental vacation and “get away “from all the worries of tomorrow. 
 
Optimal number of hours per night
The average adult needs between 7-8 hours a night. It is different for adolescents and children who on average need anywhere between 9-11 hours of sleep. When adults get less then 6 hours of sleep a night they throw there bodies into metabolic disarray. Getting 4-5 hours can actually start to do some real damage with disturbing glucose regulation and the possibility of accidents rise.
 
When it comes to sleeping, take a look at the quality of your sleep.  It is such an important component to the overall package of good health and wellness.

Janet Bertrand is a personal fitness trainer at Fitness Quest 10 who loves to motivate and inspire people to achieve their goals. Working with a diverse range of fitness levels, Janet believes the power to create change in one’s life is already there, just waiting to be tapped into.