Healthly Perspective by Linda King

How important is a good night's sleep?

Imagine these two scenarios:

A.  Awake off and on all night, you get up, walk around, go back to bed, hoping the act of closing your eyes will lead to finally falling asleep. The 6 a.m. alarm jolts you up. This is how your day starts. Your feet hit the floor and slowly, lethargically, you lift what feels like 5000 pounds off the bed and shuffle into the morning.

B.  In bed at a decent hour, snuggle under the covers, gently drifting off within 10 or 15 minutes. When the 6 a.m. alarm buzzes, you drift into consciousness, the shadows of your dreams fading into the ether. You jump out of bed refreshed, ready to attack the day.

On average, which is more like you? If "A" is more like you, how does your day go? After 5 cups of double-latte espresso with extra shots, do you feel much better? Do you hit that 3:00 o'clock wall in the afternoon? Does that afternoon snack really help to restore energy?

Feeling like this, imagine taking a spin class. Or kickboxing. Or lifting. How well do you think you'll do? Will you get maximum performance out of your body? Keep reading and find out.


As you sleep, your body enters different stages of rest. The fourth stage of sleep is called delta wave sleep, and this is when your body produces the most muscle building hormones. Sports physiologist Dr. David Ryan recommends that you sleep for 4.5, 6, 7.5 or 9 hours every night. By sleeping one of these time amounts, you'll maximize the number of times you enter delta wave sleep and you'll wake up in a lighter stage of sleep so you feel rested in the morning.


Human growth hormone, or HGH, is one of the most essential hormones your body releases to aid in muscle recovery and growth. The HGH levels in your blood are at their highest about two hours after you fall asleep. Having a sustained high level of HGH in your blood increases your muscles' capacity to absorb amino acids from protein, which in turn facilitate more muscle growth.

Cortisol is a hormone in your body that your adrenal glands release. According to the International Sports Science Association, cortisol functions as a counter to testosterone, human growth hormone and other muscle building hormones by breaking down your muscle tissue to release amino acids for energy.

Glycogen is the form of glucose that your body stores for your muscles to use as energy later. If you don't get a sufficient amount of sleep, you may begin to slow down how well you store glycogen. This means that during your next workout, you may run out of fuel halfway through. Not only does this limit your capacity for an effective exercise routine, but it may also increase your body's production of cortisol as it strains to find a replacement energy source.


Oh, but it IS a big deal. Sleep not only regulates hormone production. If you don't get enough quality sleep, a world of hurt can affect your body. These include:

Impaired glucose tolerance: Without sleep, the central nervous system becomes more active, inhibiting the pancreas from producing adequate insulin, the hormone the body needs to digest glucose. "In healthy young men with no risk factor, in one week, we had them in a pre-diabetic state," says researchers Van Cauter when referring to a study that he conducted on the effects of sleep deprivation.

Possible link to obesity: This is due to the fact that much of people's growth hormone is secreted during the first round of deep sleep. As both men and women age, they naturally spend less time in deep sleep, which reduces growth hormone secretion. Lack of sleep at a younger age, however, could drive down growth hormone prematurely, accelerating the fat-gaining process. In addition, there is also research that indicates a lowering of the hormone testosterone as well as fat gain and muscle loss.

Increased carbohydrate cravings: Sleep deprivation negatively affects the production of a hormone called leptin. This hormone is responsible for telling the body when it is full. However, with decreased production of this hormone, your body will crave calories (especially in the form of carbs) even though its requirements have been met. Not a good situation to be in for anyone wanting better health.

Weakened immune system: Research indicates that sleep deprivation adversely affects the white blood cell count in humans as well as the body's ability to fight infections.

Increased risk of breast cancer: Richard Stevens, a cancer researcher at the University of Connecticut Health Center, has speculated that there might be a connection between breast cancer and hormone cycles disrupted by late-night light. Melatonin, primarily secreted at night, may trigger a reduction in the body's production of estrogen. But light interferes with melatonin release (recall that the hormone is secreted in response to a lack of light), allowing estrogen levels to rise. Too much estrogen is known to promote the growth of breast cancers.

Hardening of the arteries: Some studies suggest that the stress imposed on the body due to lack of sleep causes a very sharp rise in cortisol levels. Such an imbalance can lead to hardening of the arteries, increasing the risk of heart attacks.  In addition, we know that very high cortisol levels lead to muscle loss, increased fat storage, loss of bone mass, depression, hypertension, insulin resistance (the cells in the body lose the ability to accept insulin), and lower growth hormone and testosterone production.

Depression and irritability: Lack of sleep also causes depletion of neurotransmitters in the brain that are in charge of regulating mood. Because of this, sleep deprived people have a "shorter fuse" and also tend to get depressed more easily.


You need 7-9 hours of sleep each night (8 being the ideal) in order for your body to run efficiently. Deprive your body of sleep and you'll have lousy fat loss and hinder your body's ability to increase lean muscle tone. Without enough sleep the body stops producing anabolic hormones (muscle producing/fat burning hormones, e.g. testosterone and growth hormone) and starts increasing the production of catabolic hormones (muscle destroying/fat depositing hormones, e.g. cortisol).

To make matters worse, you'll also lose muscle, which lowers your metabolism. In addition, you will lack the energy and focus to get through your workouts, which might lead to overtraining. To top it off, research indicates that lack of sleep creates cravings and binges in addition to hardening of the arteries, which leads to heart attacks.

Turn off the TV, the laptops, the notebooks, the cellphone, turn down the lights one hour before bed, and slowly ease your way under the covers.

Sources cited: Getting Better Between the Sheets; Dr. David Ryan Controlling Muscle Breakdown; International Sports Science Association

"Gold's Gym Mass Building Training and Nutrition System"; Ed Connors, Peter Grymkowski and Tim Kimber; 1992

Colorado State University: Growth Hormone; R. Bowen; December 2006

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