Chapter 7 Energy Balance and Obesity Calories In vs Calories Out Weight management is related to kcal in vs kcal out Discuss role of calories in to calories burned in weight management or weight loss To maintain body weight o Consume as many kcal as expended in a day In order to lose weight o Consume less kcal than what we are expending To gain weight o Consume more kcal expend less o BUT workout more for healthy gains Overall goal o Gain maintain muscle o Healthy fat stores Calories In The Food We Eat List characteristics of food that may contribute to excess calorie intake Fast food drive through and convenience foods may contribute excess kcal from o Fat and sugar Foods that are marketed as low fat or fat free can be deceiving They may have additional kcal added to them replacement sugars may be lesser in nutrients Other reasons for excess kcal o Larger portion sizes portion control problem o Easy to do when we dine out DK what healthy portion size is Calories Out Energy Expenditure Individuals vary widely in the number of calories burned each day However everybody expends energy or calories in three ways o Resting energy expenditure REE o Physical activity o Thermic effect of food TEF o Altogether this is Total energy expenditure Components of total energy expenditure List and describe the components of total energy expenditure Energy metabolism that occurs after waking in the morning at least 12 hours after the last meal o Basal Metabolic Rate o Includes energy for functions that sustain life Breathing Heart beat Brain while sleeping too Liver Kidneys filtering blood Less restrictive measure of calories burned while just sitting or sleeping and also make up most of the calories we burn in a day BMR but less restrictive o Resting Energy Expenditure REE requires 12 hour fast Components of Total Energy Expenditure Energy expenditure through voluntary physical effort including daily activities exercise or physical labor o Physical activity Energy needed for muscle contraction o The more muscles you contract and the more frequently you contract them the more calories you burn List the factors that may influence the amount of energy expended during exercise Factors that influence energy burned during exercise o Body weight and muscle mass in use o Duration of activity o Intensity of the activity o Exerciser s fitness level o Type of activity determines how much energy is used planned and unplanned muscle contraction Components of Total Energy Expenditure The process of burning calories as you digest absorb transport store and metabolize food fairly constant o Thermic Effect of Food TEF o Research shows that your body burns about 10 percent of calories consumed depending on the type and quantity of food eaten Diet can have a mild influence o A little higher for protein about 10 o A little lower for fat o Look at 7 4 but don t need to memorize of three components we have the most influence over physical activity Total Energy Expenditure o TEE estimated by energy equation formulas and factors based on level of physical activity o Women 665 1 9 563 x weight in kg 1 850 x height in cm 4 676 x age o Men 66 5 13 75 x weight in kg 5 003 x height in cm 6 775 x age o Multiply for physical activity factor Table 7 5 o Sedentary BMR x 1 2 o Lightly active light exercise 1 3 days week BMR x 1 37 o Moderately active moderate exercise 3 5 days week BMR x 1 55 o Very active hard exercise 6 7 days a week BMR x1 725 o Extra active very hard exercise and physical job BMR x 1 9 o Don t need to memorize formulas they calculate REE then plug value in physical activity factor Total Energy Expenditure Compare the differences between the components of total energy expenditure between a sedentary and physically active person Body Mass Index BMI Define BMI and determine if an individual is considered underweight normal weight overweight or obese based on their BMI o The body mass index BMI is a measure of weight relative to height Often used to diagnose overweight or obesity o Standard formula to calculate BMI o Weight in kilograms height in meters squared Discuss the relationship between BMI and the location of excess body fat o Result may suggest degree of excess body fat o Under 18 5 underweight o 18 5 24 9 normal weight o 25 29 5 overweight o Over 30 obese BMI and Disease Risk List conditions that the risk for increases in those who are overweight and underweight o Being overweight or obese raises the risk for a number of diseases such as o Cardiovascular disease o Hypertension o Type 2 diabetes o Stroke o Gallbladder disease o Osteoarthritis o Sleep apnea o Respiratory problems o Endometrial breast prostate and colon cancers BMI and Mortality Discuss the risk of chronic conditions and mortality Underweight o o o o o o o o o o A BMI 18 5 kg m2 is considered to be Underweight Negative consequences of being underweight may include Decreased overall energy Respiratory complications Heart irregularities Infertility Weakened immune system Delayed wound healing Underweight Define osteoporosis and list the risk factors for developing osteoporosis o A condition associated with decreased bone mass and bone density that can result in increased risked of bone fracture is o Osteoporosis o Those at greater risk for osteoporosis includes o o o o o Identify individuals for whom BMI may not accurate screen for overweight or obesity Limitations of BMI o Limitations of BMI fails o Does not distinguish between fat and muscle mass Taking into account height and weight o Other ethnicities o Elderly o Sex male female Body Composition o o o o o o o Total body mass is the sum of lean tissue mass fat mass and water There are categories of body fat The fat required for normal physiological functioning Essential fat Fat from adipose tissue tissue under the skin and the fat that pads essential organs Storage fat Percent of weight from fat differs with age and sex Body fat usually increases with age Women should have a higher body fat percentage than men Body Composition o o o Body Fat Distribution o o o Fat women have higher body mass percentage pregnancy Muscle men have higher body mass percentage Bone men have higher body mass percentage taller There are two kinds of distributions Gynoid pattern pear shape Fat over the muscle and under the skin at hips and thighs Subcutaneous fat Android pattern apple shape Body fat can be stored under the abdominal muscle around the internal organs Visceral fat Associated with increased risk