So aside from making you irritable, less productive, and just generally unpleasant to be around, lack of sleep can have effects on your body composition. That’s because getting less than 7 hours of sleep during the night will elevate your levels of the stress hormone, cortisol. Here is some information on cortisol and how it affects the body.

Cortisol is a stress hormone. Your body produces cortisol in response to stress, physical, mental or emotional. This can include extremely low calorie diets, lack of quality sleep as well as common daily stresses such as job pressures.

What does cortisol do?
Cortisol is part of the fight or flight response. Faced with a “life or death” situation, cortisol increases the flow of glucose (as well as protein and fat) out of your tissues and into the bloodstream in order to increase energy and physical readiness to handle the stressful situation or threat.

Is cortisol related to abdominal obesity?
Yes. There is a link between high cortisol levels and storage of body fat, particularly “visceral” abdominal body fat (also known as intra-abdominal fat). Visceral fat is stored deeper in the abdominal cavity and around the internal organs, whereas “regular” fat is stored below the skin (known as subcutaneous fat). Visceral fat is particularly unhealthy because it is a risk factor for heart disease and diabetes.

Is cortisol is bad for you?

Chronically elevated cortisol levels may have a variety of negative effects. Cortisol is catabolic and elevated cortisol levels can cause the loss of muscle tissue by facilitating the process of converting lean tissue into glucose. An excess of cortisol can also lead to a decrease in insulin sensitivity, increased insulin resistance, reduced kidney function, hypertension, suppressed immune function, reduced growth hormone levels, and reduced connective tissue strength. Chronically elevated levels of cortisol can also decrease strength and performance in athletes.

How can you lower your cortisol levels naturally?

-Avoid very low calorie diets, especially for prolonged periods of time. Low calorie dieting is a major stress to the body. Low calorie diets increase cortisol while decreasing testosterone.

-Avoid overtraining by keeping workouts intense, but brief (cortisol rises sharply after 45-60 min of strength training)

-Get plenty of quality sleep (minimum of 7 hours for most adults, some will require more)

Chrousos, G.P., The role of stress and the hypothalamic-pituitary-adrenal axis in the pathogenesis of the metabolic syndrome: neuro-endocrine and target tissue-related causes. International Journal of Obesity and Related Metabolic Disorders, 2000

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Wednesday’s WOD:

Run 400 meters
Perform as many Thrusters as possible
Run 800 meters

This workout has a 12 minute time limit.  You must finish the final 800 meter run before the 12 minutes expire.

Start with a 400 meter run

then perform as many Thrusters as possible with the remaining time.  However, leave enough time to run (1) 800 meter run before the 12 minutes expires.  You decide how many thrusters you do and how much time you leave in order to complete the 800 meter run.

Score is the number of Thrusters completed.  Your score is “disqualified” if you don’t make it back before the 12 minutes expire.

The concept of this workout was created by Mike M., trainer/owner of CrossFit Oakland.

results:

Performance props to Helen for getting her first muscle up and being the first female at the Sweat Shop to get a muscle up!

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