minimum 8 hrs per night is optimal.

brain needs adequate recovery to function properly, including areas involved in decision making and memory.

beneficial for preventing disease, improving physiological well-being, and improving fitness.

60 min recommended per day.

Limit to 1 beverage/day.

red wine appears to have beneficial effect.

Steroid hormones

Amino acid or protein hormones

alter the activity of "target cells" by changing either:

1. protein synthesis

2. rate of enzyme activity and secretory activity

3. plasma membrane transport

• Secreted from the adrenal medulla
• Released as neurotransmitters by the SNS.
• Increase heart rate and heart muscle contraction force.
• Increases skeletal muscle blood flow.
• Decrease at a given absolute intensity with exercise training
• Stimulates glycogen breakdown in muscle and fat breakdown in fat cells. 

• The hypothalamus secretes cortisol.
• A normal response to emotional stress, trauma, infection, surgery, and physical exertion such as resistance training. 
• Cortisol decreases amino acid transport into cells, in turn blunts anabolism and stimulates the breakdown of proteins. 
• High levels lead to excessive protein breakdown and negative nitrogen balance.
• Serves as an insulin antagonist inhibiting glucose uptake and oxidation.

• Primarily secreted by the testes.
• Promotes protein synthesis and muscle growth.
• Increases during exercise.
• The conversion of testosterone to estrogen provides males with significant protection in the maintenance of bone structure throughout life.

• Primarily secreted from the ovaries.
• Contributes to vasodilation, the relaxation of blood vessels leading to increased blood flow, and is an antioxidant.
• Stimulates calcium deposits in the bone.
• Provides protection in females from heart disease progression and osteoporosis. 

• Secreted from the beta cell of the pancreas in response to food intake. 
• Insulin is a hormone that stimulates acute metabolic responses in a variety of body tissues.
• Primary function: signals insulin sensitive tissues, e.g. skeletal muscle and adipose tissue to take up glucose from the blood, which lowers the blood glucose levels and increases glucose utilization.
• Increases the synthesis of fat and decreases during exercise. 

• Increases blood glucose.
• Increases at onset of exercise.
• Increases protein and fat breakdown.
• Increases in response to protein intake. 

• One of the most important processes of life and it is regulated by the nervous, cardiovascular, and endocrine system. 
• Stressors cause homeostatic disruption and negative feedback is a common regulatory system to reinstate homeostasis. (analogy to thermostat)
• Ex. regulate body temp at 98.6 by sweating to release heat or shivering to produce heat. 
• Ex. regulate blood pressure in a very narrow range. Signals from the brain cause the heart to pump faster or slower, and blood vessel diameter changes to maintain pressure. 

• Glucose is normally used by the brain for appropriate nervous system function as well as in other tissues. 
• Homeostasis keeps blood glucose between 70-100 mg/dl. 
• Obtained from carbohydrates in foods.
• Glucagon: causes the release of glucose from the liver into the blood and insulin: cause cells to absorb glucose from the blood.

• Food intake → blood glucose level increases → pancreas releases insulin → stimulates primarily muscle to take up glucose → blood glucose decreases. 
• Fasting → pancreas releases glucagon → stimulates liver to release glucose → blood glucose increases

• The diet is composed of 3 macronutrients:
  
  • Protein, fat, and carbohydrate.
• Macronutrients provide energy in the form of calories.
• Alcohol also has calories: 7 kcal/gm.

• micronutrients are not energy providing, although they may be participants in energy producing pathways: vitamins and minerals

• Sum of all chemical reactions taking place in the body.
• Nutrients need to be obtained to adequately perform metabolism.

• Energy is the capacity to do work.
• One dietary calorie is defined as the quantity of heat necessary to raise the temperature of one kilogram of water one degree Celsius. 

• two ways to reduce caloric intake is to decrease fat and refined sugar intake.
• many packaged foods contain high quantities of refined carbohydrates. 
• eating fruits and vegetables in their natural state can help reduce caloric intake. 

• is a grain milled in its entirety, and includes the bran, germ and endosperm.

• is a food where all the coarse parts have been removed. 
• bran, germ and husk have been removed, leaving only the endosperm.

• are processed foods that have some nutrients added back. 
• Ex. rice, spaghetti, cereals, and pastas. 
• fails to compensate for losses of many other nutrients and fiber.

1. fats →  broken down for energy or stored as body fat.
2. carbohydrate →  broken down for energy or stored as glycogen.
3. protein →  broken down or used to make body proteins.