EXCI252Ch9DesigningWeightManagementBodyCompProgramsF2023Part1.pptx

Chapter 9 Designing Weight Management & Body Composition Programs Part 1 EXCI 252 1 Definitions of Obesity  is an excessive amount of body fat relative to body weight.  is a BMI greater than or equal to 30 kg/m2 in adults (US DHHS, 2000b).  is a BMI greater than or equal to the 95th per...

Chapter 9 Designing Weight Management & Body Composition Programs Part 1 EXCI 252 1 Definitions of Obesity  is an excessive amount of body fat relative to body weight.  is a BMI greater than or equal to 30 kg/m2 in adults (US DHHS, 2000b).  is a BMI greater than or equal to the 95th percentile for age & sex according to the US CDC and Prevention growth charts developed for children and adolescents.  These definitions:  are not universally accepted.  do not take into account the composition of an individual’s body weight. EXCI 252 2 Definitions of Obesity  US CDC & Prevention BMI Growth Chart (2 to < 20 years of age)  Example: 10-year-old boy.  Obese:  BMI ≥ 95th percentile  Overweight:  BMI = 85th to < 95th percentile  Healthy weight:  BMI = 5th to < 85th percentile  Underweight:  BMI < 5th percentile EXCI 252 3 Prevalence of Overweight & Obesity  Global Pandemic  Obesity: > 600 million adults.  about 13% of the world’s population (WHO, 2016).  Overweight: > 1.9 billion adults (WHO, 2016).  Overweight prevalence is variable in some countries:  < 20% in Afghanistan, India,, Indonesia, & most countries in Africa.  > 60% in Australia, Canada, USA, & nearly all of Europe.  United States  Obesity: 36.5% adults, & 17% of youth.  Severely obese: 6.6% of adults in 2010  Overweight & obese children & adolescents (6-19 yr): about 34% (Ogden, 2014). EXCI 252 4 Obesity & Overweight Americans Adult Ages 20-74 13% 14% 15% 23% 31% 30% = 43% 32% = 46% 32% = 47% BMI ≥ 30 = 56% 33% 34% = 65% BMI = 25.0-29.9 (CDC, 2005) EXCI 252 5 Prevalence¶ of Self-Reported Obesity Among U.S. Adults, BRFSS, 2022 Prevalence reflects BRFSS methodological changes started in 2011. These estimates should not be compared to prevalence estimates before 2011. ¶ *Sample size < 50 or the relative standard error (dividing the standard error by the prevalence) ≥ 30%, or no data in a specific year. EXCI 252 9 Estimated Prevalence of Obesity in Canadian Adults by Province (2005-2017/18) Adults with BMI ≥30 kg/m2 in each province as calculated from the self-reported height & weight surveys conducted by the Canadian Community Health Survey (CCHS). Source: Lytvyak, E. et al. Trends in obesity across Canada from 2005 to 2018: a consecutive cross-sectional populationbased study. CMAJ OPEN 10 (2): E439-eE449 2012, DOI:10.9778/cmajo.20210205. EXCI 252 7 Risks of Obesity  Cardiovascular ischemic HD  Insulin resistance  Stroke  Diabetes mellitus  Dyslipidemia  Obstructive pulmonary disease  Hypertension  Gallbladder disease  Glucose intolerance  Osteoarthritis EXCI 252 8 Risks of Obesity Cancers of the:  Colon  Endometrium  Prostate  Cervix  Ovary  Esophagus  Breast  Gallbladder EXCI 252 9 Risks of Being Underweight  Fluid-electrolyte imbalances  Cardiac arrhythmias  Osteoporosis  Sudden death  Osteopenia  Peripheral edema  Bone fractures  Renal disorders  Muscle wasting  Reproductive disorders EXCI 252 10 Obesity  Total Body Fat  Body Fat Distribution EXCI 252 11 Types of Obesity  Android  Gynoid Obesity  upper-body obesity  apple-shaped  more typical of males  some women Obesity  lower-body obesity  pear-shaped  more typical of females  some men EXCI 252 12 Obesity  has several possible etiologies.  subtypes exist:  Metabolically Healthy, but Obese (MHO)  Metabolically Obese, but Normal Weight (MONW)  Metabolically Unhealthy & Obese (MUHO) EXCI 252 13 Differences in Metabolic Characteristics of MHO, MUHO, MONW, & MH Individuals Variable MHO MUHO MONW MH BMI High High Low Low Visceral Fat Low High High Low Fat Mass High High High Low Lean Body Mass - - Low High Liver Fat - - High Low Insulin Sensitivity High Low Low High HDL-C High Low Triglycerides Low High High Low MH = Metabolically Healthy (Karelis et al., 2004; J. Clin. Endocrinol. Metab. 89: 2569-2575.) EXCI 252 14 Causes of Overweight & Obesity  Physiological Factors  Developmental Factors  Genetic Factors  Lifestyle Factors  Psychosocial Factors EXCI 252 15 Physiological Factors  Metabolism & Energy Balance  Hormones EXCI 252 16 Energy Need & Energy Expenditure  are measured in kilocalories (kcal).  Kilocalorie (kcal)  is defined as the amount of heat needed to raise the temperature of 1 kg (2.2 lb) of water 1o C.  Direct Calorimetry  is used to measure the energy yield & caloric equivalent of various foods.  Indirect Calorimetry  is used to measure energy expenditure during basal, resting, or activity states.  energy expenditure is estimated from O2 utilization.  1 L O2 = 5 kcal expended. EXCI 252 17 Energy or Caloric Need  is a function of an individual’s  metabolic rate, &  physical activity level. EXCI 252 18 Energy Yield & Caloric Equivalents for Macronutrients Direct Calorimetry Nutrient Energy Yield (kcal·g-1) Caloric Equivalents (kcal·L O2-1) Carbohydrate 4.1 5.1 Protein 4.3 4.4 Fat 9.3 4.7 EXCI 252 19 Basal Metabolic Rate  is a measure of the minimal amount of energy (kcal) needed to maintain basic & essential physiological functions such as breathing, blood circulation, & temperature regulation.  varies according to age, gender, body size, & body composition.  is assessed in a rested & fasted state (at least 12 hours) & in a controlled environment.  is not always practical to measure, therefore the resting metabolic rate (RMR) is assessed. EXCI 252 20 Resting Metabolic Rate  or resting energy expenditure (REE).  is the energy required to maintain essential physiological processes in a relaxed, awake, & reclined state.  is slightly higher (10%) than BMR.  is measured 3-4 hours after a light meal without prior physical activity.  is the largest component of metabolism.  can be measured using indirect calorimetry by estimating the body’s energy expenditure from oxygen utilization.  1 liter of oxygen consumed = 5 kcal. EXCI 252 21 Total Energy Expenditure  BMR: Basal metabolic rate  RMR: Resting metabolic rate  DT: Dietary thermogenesis  energy needed for digesting, absorbing, transporting, & metabolizing foods.  PA: Physical activity = EAT + NEAT  EAT: Exercise activity thermogenesis  NEAT: Non-exercise activity thermogenesis  energy expenditure of occupation, leisure, activities of daily living, & unconscious or spontaneous motion such as fidgeting (Aragon et al., 2017). EXCI 252 22 Total Energy Expenditure  TEE = BMR + DT + PA  TEE = BMR + DT + EAT + NEAT  TEE = RMR + DT + PA  TEE = RMR + DT + EAT + NEAT EXCI 252 23 Components of TEE TEE Component % TEE BMR 60 - 70 Dietary Thermogenesis 8 - 15 EAT 15 - 30 NEAT 15 - 50 Source: Aragon, A.A., Schoenfeld, B.J., Wildman, R., Kleiner, S., VanDusseldorp, T., Taylor, L., Earnest, C.P., Arciero, P.J., Wilborn, C., Kalman, D.S., Stout, J.R., Willoughby, D.S., Campbell, B., Arent, S.M., Bannock, L., Smith-Ryan, A.E., and Antonio, J. International society of sports nutrition position stand: Diets and body composition. Journal of the International Society of Sports Nutrition 14: 16, 2017. EXCI 252 24 Measurement of TEE  Doubly-Labeled Water Method  with deuterium & oxygen-18      gold standard expensive requires considerable expertise requires specialized equipment Prediction Equations  estimate TEE  age- and gender-specific EXCI 252 25 Measurement of TEE  Indirect Calorimetry  For specific physical activities, EE is typically expressed in METs as a multiple of the RMR.  1 MET  = relative rate of O2 consumption (3.5 mL·kg-1·min-1)  = relative rate of energy expenditure (1.0 kcal·kg-1·hr-1)  Digital Activity Log  allows the client to record the type & duration of physical activity performed during the day in a handheld computer. EXCI 252 26 Factors Affecting RMR 1. Heredity & Environment 2. Hormones  Underproduction of thyroxine can reduce RMR 30 to 50%.  GH, epinephrine, & norepinephrine, & various sex hormones released during exercise may elevate RMR as much as 20%. 3. Age  RMR decreases 2 to 5 % during each decade of life after 25 years of age. 4. Gender (Sex)  Men > Women  is due to higher proportion of muscle mass & a smaller proportion of fat mass. EXCI 252 27 Factors Affecting RMR 5. Body Composition  For the same body weight, a muscular individual has a greater RMR than a fatter individual. 6. Body Size  An individual with a larger body size or body surface area has a larger RMR than an individual with a smaller body size or body surface area. 7. Weight Loss  Dieting decreases RMR. 8. Weight Gain  Overeating regularly increases RMR. 9. Exercise  Increased energy expenditure increases RMR. EXCI 252 28 Energy Balance  Static Energy Balance Approach  Assumes that a change in 1 side of the energy balance (EB) equation does not change or influence the other side of the equation.  Dynamic Energy Balance Approach  Assumes that numerous biological & behavioural factors regulate & influence both sides of the EB equation.  Assumes that a change in 1 side of the equation can & does influence the other side of the equation. (Source: Manore, M.M. Rethinking Energy Balance: Facts You Need to Know About Weight Loss and Management. ACSM Health & Fitness Journal 19(5): 9-15,2015.) EXCI 252 29 Static Energy Balance Food Exercise  Describe a person who is in a positive energy balance.  Describe a person who is in a negative energy balance. Energy In = Energy Out EXCI 252 30 Static Energy Balance  Energy Balance  Caloric intake = Caloric expenditure  Energy Imbalance  Results in weight gain or weight loss  3500 kcal = 1 lb of fat  Positive Energy Balance  Caloric intake > Caloric expenditure  (Food intake) > (Resting metabolism + Physical activity level)  Negative Energy Balance  Caloric intake < Caloric expenditure  Reduce food intake and/or increase physical activity level EXCI 252 31 Static Energy Balance  Wishnofsky’s Rule  The caloric equivalent of 1 lb of body weight lost is approximately 3500 kcal.  After reviewing weight loss in obese, sedentary individuals who typically consumed low-calorie, high-protein diets within a clinical setting (Source: Manore, M.M. Rethinking Energy Balance: Facts You Need to Know About Weight Loss and Management. ACSM Health & Fitness Journal 19(5): 9-15, 2015.) EXCI 252 32 Static Energy Balance  A cumulative energy deficit of 3500 kcal is required to lose 1 pound of body weight.  Assumption      The exclusive loss of adipose tissue Each lb of adipose tissue contains ~ 87% fat 1 lb = 454 g Therefore, 87% (454 g) = 394.98 = 395 g 395 g x 9 kcal/g = 3555 kcal EXCI 252 33 Static Energy Balance Equation Steps for Designing a Weight Loss Program (Page 296) 6. Plan to produce a calorie deficit of 700 to 800 kcal per day by reducing the calorie intake by 500 kcal per day and increasing the calorie expenditure by 200 to 300 kcal per day through exercise. To calculate caloric expenditure during exercise, refer to appendix E.3. Multiply the calories burned per minute per kilogram of body weight by the duration of the activity and the client’s body weight. Continue this program until the total calorie deficit of 35,000 kcal is reached. In a little over 7 wk the client will lose approximately 10 lb (4.5 kg). This is a gradual average weight loss of 1 1/2 lb (0.7 kg) per week. Reassess the body composition to see if the percent fat goal was reached. EXCI 252 34 Static Energy Balance Equation  Refer to the Steps for Designing a Weight Loss Program on pages 296 & 297 of your textbook. Variable Before Modification After (kcal) (kcal) (kcal) Daily Energy Intake 2000 - 500 1500 Daily Energy Expenditure 1817 + 300 2117 Balance (Net) + 183 800 - 617 Comment Surplus EXCI 252 Deficit 35 Static Energy Balance Equation  Refer to the Steps for Designing a Weight Loss Program on pages 296 & 297 of your textbook. Variable Before Modification After (kcal) (kcal) (kcal) Daily Energy Intake 2000 - 630 1370 Daily Energy Expenditure 1817 + 353 2170 Balance (Net) + 183 - 800 Surplus Deficit Comment  The energy intake should not be less than 1200 kcal per day.  The caloric deficit should be equal to or less than 1000 kcal per day. EXCI 252 36 Static Energy Balance Equation  Lose 10 lb of body weight assuming that the loss is exclusively fat:  Total Caloric Deficit = 10 lb x 3500 kcal/lb = 35000 kcal  Caloric Deficit / Day = 800 kcal/day  Caloric Deficit / Week = 800 kcal/day x 7 days/week = 5600 kcal/week  Number of weeks = 35000 kcal / 5600 kcal/week = 6.25 weeks EXCI 252 37 Dynamic Energy Balance  The number of kcal required for 1 lb of weight loss changes depending on the duration of the dieting period, type of diet, & physical activity level. (Source: Manore, M.M. Rethinking Energy Balance: Facts You Need to Know About Weight Loss and Management. ACSM Health & Fitness Journal 19(5): 9-15,2015.) EXCI 252 38 Dynamic Energy Balance  Researchers at the National Institutes of Health (NIH) and the Pennington Biomedical Research Center (PBRC) have developed mathematical models to better predict weight change using the dynamic energy balance model.  The mathematical models can be found at the following websites:  NIH Model   https://www.niddk.nih.gov/bwp PBRC Model  https://www.pbrc.edu/research-and-faculty/calculators/weight-loss-predictor/ EXCI 252 39 Genetic Factors  Genes influence: 1. Body size & shape, 2. Body fat distribution, 3. Metabolic rate, 4. The ease with which weight is gained as a result of overeating & the location on the body extra weight is added. EXCI 252 40 Genetic Factors  Normal Weight Parents  10% of children were obese  Overweight Adolescents  70% chance of becoming overweight adults  1 or Both Parents are Overweight or Obese  80% probability that adolescents become obese adults EXCI 252 41 Genetic Factors  Genes influence not only weight gain but also how and where excess body fat is deposited.  Normal BMI & Lower SAT:VAT ratio     A metabolically obese phenotype Characterized by an increased VAT relative to SAT Store excess fat viscerally rather than subcutaneously Increases the risk for metabolic & cardiovascular disease  Higher BMI & Higher SAT:VAT ratio    Characterized by a decreased VAT relative to SAT Store excess fat subcutaneously rather than viscerally Lowers the risk for metabolic & cardiovascular disease EXCI 252 42 Genetic Factors  Approximately 25% of the variability among individuals in absolute & relative body fat is attributed to genetic factors.  30% of the variability is associated with cultural (environmental factors).  Much of the interindividual variability in body weight is attributable to the interactions between:  genes & environment, or  genes & behaviour. EXCI 252 43 Developmental Factors  Obesity is associated with fat cell  hyperplasia (an in fat cell number),  hypertrophy (an in fat cell size). Classification Normal-Weight Obese Fat Cell # Fat Cell Size 25-30 billion 42-106 billion EXCI 252 40% > non-obese 44 Developmental Factors  Traditional Theory  The number of fat cells:  is set during childhood & adolescence.  remains constant in both lean & obese adults.  does not change throughout adulthood.  Weight Gain  Hypertrophy of adipocytes.  Weight Loss  Atrophy of adipocytes. EXCI 252 45 Developmental Factors  New Theory  Tchoukalova & Colleagues (2010)  Induced a body fat gain of about 4 kg in normal-weight adult men & women.  Adipocytes experienced:  Hypertrophy in the upper body, and  Hyperplasia in the lower body. EXCI 252 46 Psychosocial Factors  Psychological  Social Factors (stress) Factors  Cultural Factors EXCI 252 47