BODY COMPOSITION ASSESSMENT Flashcards

Question

What is the average body fat (percentage ) in men vs women. what change is seen in body fat as we age?

Answer 1

Average Body fat; Young adult men: 12-15% (total fat) Young adult women: 25-28% -No systemic evaluation exists for body composition of the general population to warrant establishing norms or precise recommended values for body composition -The general trend indicates a tendency for percentage body fat to steadily INCREASES with advancing age (even when exercising at older age)

Answer 2

Goal body weight (Kg)= Fat-free body mass divided by (1.00- desired %fat) fat mass= body weight x percent body fat fat-free body mass= body weight - fat mass Goal weight = fat free body mass % (1.0- 0.15) = ex: 85.6 kg(goal weight) and 91 kg is body weight.

Answer 3

Obesity Prevalence: - 140 milion Americans are either overweight or obese - Overweight occurrence is higher in women and minority groups - 34% of adult population classify as Obese - Worldwide 310 million are obese and 775 million are overweight - OBESITY is the second leading cause of preventable deaths in United States - Annual cost estimated at $140 billion

Answer 4

Obesity in children -In the last 30 years, childhood obesity has Tripled among children ages 6 to 11 to more than 15% -rate have doubled for ages 2-5 (>10%) and 12-19 (15%) -Overweight children and adolescents, regardless of final body weight, exhibit higher risk of illnesses as adults than adolescents of normal weight -Overall, 32% of children are overweight or obese -16% obese 11% extremely obese

Answer 5

2-19 17% of children are overweight women tend to be more overweight as we age -adults -35-36% of all men and women are obese or overweight in U.S. As women age, women gain weight due to menopause.

Answer 6

12.5 million children are overweight or obese 77.5 million of adults age 20 and older are overweight or obese obesity and BMI also increasing in Europe (especially in Greece and Yugoslavia)

Answer 7

Overfatness -long term process Overfatness represents a Heterogeneous disorder in which Energy INTAKE EXCEEDS energy Expenditure Disruption in energy balance often begins in Childhood, which INCREASES the chance for adult obesity considerably between ages 20 and 40, Americans gain about 2 pounds a year for a 40-pound gain in body weight -Women tend to gain the MOST weight

Answer 8

Reasons for Classifying overweight and obesity: -Provides meaningful comparisons of body weight status within and between populations -Identifies Individuals and groups at increased risk of morbidity and mortality -Identifies priorities for intervention at the individual and community levels -Establishes a firm basis for evaluating diverse intervention strategies it will help ID individuals at risk for comorbidities, and intervene and help decrease morbidity, mortality long term

Answer 9

Genes are involved in causing obesity: also different organs produce substances or hormones that lead to obesity: GI tract Adipose tissue create Leptin Stomach produces Grehlin pancreas produces insulin these organs and dopamine and serotonin all input into nervous system and affect your desire for food.

Answer 10

Overeating: -A general INCREASE in energy intake has occurred over a 30-year period among adult Americans -Adult women eat 335 more Kcal per day now than they did in 1970; Men eat 168 calories more -Yearly increase: Women= 122,275 men= 61, 320 -Overeating has increased because of portion size increases, and availabity of pre-prepared foods contribute to higher caloric intake.

Answer 11

Genetics and Fat accumulation - Research with twins, adopted children, and specific segments of the population attribute up to 80% of the risk of becoming obese to genetic factors - If a child under age 10, regardless of current weight, has one or both obese parents, the child has More than TWICE the normal risk of becoming an obese adult. - Genetic makeup does NOT necessarily cause obesity, but instead LOWERs the threshold for it. - In an Obesity-producing environment- Sedentary and stressful, with ready access to inexpensive, large-portion, high-calorie , good-tasting food-- the genetically susceptible individual gains weight.

Answer 12

-researchers now link human obesity to some Mutant genes -The linkage of genetic and molecular abnormalities to obesity allows researchers to view overfatness as a DISEASE rather than a Psychologic flaw. Obesity genes- Leptin, Adiponectin, melanocrotin and 4 receptor

Answer 13

Leptin- obesity gene -congenital Absence of leptin, a hormonal body weight-regulating substance produced by Fat (adipose) and released into bloodstream that acts on hypothalamus, produced Continual HUNGER (always hungry) and marked obesity in studies. Neither short, nor long-term exercise meaningfully affects leptin. absence of leptin is a genetic predisposition to being obese (occur in young children) no leptin- eating and never feeling full. Leptin- normally decreases hunger.

Answer 14

Leptin process: 1. The ob gene inside a fat cell (adipose) creates Leptin 2. Leptin moves from fat cells and enters the bloodstream 3. leptin signals the hypothalamus to reduce or stop the drive to eat after reaching the "set point" for the body's total fat content

Answer 15

Adiponectin ( gene: ADIPOQ): Hormone produced by Adipocytes target: Muscle and liver cells- induces fat burning and glucose utilization -DEFECTIVE Gene variants: reduces adiponectin production

Answer 16

Defective adiponectin reduced ability to burn fat and glucose uitlization and predispose you to metabolic syndrome

Answer 17

Adiponectin targets: Liver: decrease in glucose output, fat accumulation and inflammation n Muscle; increase glucose uptake, decrease fat accumulation and increase energy expenditure -Heart: decrease inflammation, endothelia adhesion, and foam cell formation.

Answer 18

Mealnocortin 4 receptor (gene; MC4R) -G protein coupled receptor-it binds alpha-melanocyte stimulating hormone- located on paraventricular nucleus (PVN) of the hypothalamus alpha melanocyte stimulating hormone- induced by leptin -Defective gene variants: lack of satiety and early-onset severe obesity (because they are not getting feedback signal of being fed and feeling full)

Answer 19

Racial differences in food and exercise habits and cultural attitudes toward weight help explain obesity prevalence in Black women, 50% vs white women, 33% - research with obese women shows that differences in resting energy expenditure, related to racial differences in lean body mass, contribute to obesity racial differences - On average, black women burn nearly 100 fewer Kcal each day during rest than white counterparts - Total daily energy expenditure of black women averages 10% lower than whites, owing to a 5% lower REE and 19% lower physical activity energy expenditure

Answer 20

Transmissible variance for body fat: - 25% genetics - 30 % cultural transmission - 45% Nontransmissable (a lot of other factors that contribute to percent body fat)

Answer 21

Regular physical activity, recreationally or occupationally effectively IMPEDES weight gain and adverse changes in body composition - Individuals who maintain weight loss over time, shows GREATER muscle strength and engage in more physical activity than counterparts who regain lost wight - The Current National guidelines by Surgeon General and Institute of Medicine recommend a minimum of 30 to 60 minutes of moderate and physical activity daily.

Answer 22

physical inactivity or decease in regular physical activity leads to increase in obesity rates for individuals

Answer 23

health risks of Excessive Body Fat: Obesity represents an important cause of preventable death in America -Impaired glucose tolerance and a diminished quality of life emerge even in obese children and adolescents -hypertension, elevated blood sugar, postmenopausal breast cancer (may lead to atherclerosis) , elevated total cholesterol and low high-density lipoprotein (HDL) cholesterol increases there risk of or health at any given level of excess weight - Increased loads on the major joints can lead to pain and discomfort, complications form osteoarthritis, inefficient body mechanics, and reduce mobility

Answer 24

Physical fitness is good medicine: -improved physical fitness interacts with the overfat condition to lower disease risk. -men age 30 to 83 years old who are overweight but physically fit suffered fewer deaths from all causes than unfit but normal weight men -Unfit, lean mean- shows a higher risk of all-cause mortality than overfat -occurs Since you when one is fit, and does physical activity, they are overloading system and keeping muscle strength, keep bone mass and fat free mass up physical active is way more important than weight.

Answer 25

-Children who gain more weight than peers tend to become overweight adults with Increased risk for hypertension, elevated insulin, hypercholesterolemia, and heart disease The American Academy of Pediatrics: -requiring an in-depth medical assessment for overweight children (BMI > 95th percentile) -Requiring second-level screening including family history and risk factor assessment for those at risk of becoming overweight (BMII 85th -95Th percentile)

Answer 26

Specific Health risks of Excessive Body Fat: - impaired cardiac function from increased mechanical work and autonomic and left-ventricular dysfunction - hypertension, stroke, and deep-vein thrombosis increased in obese individuals - Increased insulin resistance in children an adults and type 2 diabetes (80% of these patients are overweight) - Renal disease (kidney) - Sleep apnea, mechanical ventilatory constraints (not being able to inflate lung) , and pulmonary disease form impaired function because of added efforts to move the chest wall - sleep apnea decreases quality of sleep and increase risk of Cardiovascular disease

Answer 27

Health Risks of obese individuals (excessive body fat): -problems receiving anesthetics during surgery -osteoarthritis, degenerative joint disease, and gout -Endometrial, breast, prostrate and colon cancers -abnormal plasma lipid and lipoprotein veins Menstrual irregularities (female triad, athletes who overtrain and obese inviduals have trouble having a baby) gall bladder disease -Enormous psychologic burden and social stigmatization and discriminiation obesity individuals less likely to be promoted

Answer 28

Approaches to measuring person's fat content: -percentage of body mass composed of fat -distribution of patterning of fat at different Size and number of individual fat cells

Answer 29

A norma range of body fat can be found by taking the average percentage body fat value plus or minus one standard deviation (D) -however, just because the average value percentage body at increases with age, this does NOT dictate that people should become fatter as they age. Standard for overfatness Men: >20 % body fat women will have >30% of body fat

Answer 30

Regional fat distribution - Central or Android-type obesity: - fat deposition the abdominal area, particularly internal visceral deposits - Has an INCREASED health risk - Shows GREATER metabolic responsiveness than peripheral obesity - Peripheral or GYNOID-type obesity- - waist to hip girth ratios that exceed 0.80 for women and 0.95 of men increase risk of death.

Answer 31

apples- android- have increased health risks, but greater metabolic responsiveness ; once they start exercising, belly shrinks more quickly because the adipocytes located in this central region are easy to mobilize pears- gynoid type; which have a Healthier or better distribution of fat men- apple shape (android) women- pear shape (gynoid) -

Answer 32

Adipocyte tissue mass increases in 2 ways: 1. Fat Cell Hypertrophy- Existing adipocytes will ENLARGE (size) or fill with fat 2. Fat cell Hyperplasia: Total adipocyte NUMBER INCREASES

Answer 33

Cell NUMBER represents the major structural Difference in adipose tissue mass between the severely obese and nonobese persons -As body fat increases, adipocytes eventually reach a Biologic upper limit (these adipose cells can only get so big, have limit; hence trigger point is where hyperplasia occurs) Once this occurs, cell number becomes the key factor determining any further obesity -An average sized person has 25-30 billion adipocytes, whereas the clinically severe obese may have MORE than 3-5 times this number. -for average person (you are increasing or decreasing triglyceride which leads to increasing or decreasing cell) hyperplasia occurs more in severe to morbidity obese (gain more adipose cells)

Answer 34

Effects of weight loss and Gain Loss: in adults, the major change in adipose cellularity in weight loss is SHRINKAGE of Adipocytes with NO change in cell number Gain: In general, moderate weight gain form overeating in adults ENLARGES existing adipocytes rather than stimulating new adipocyte development

Answer 35

you only increase cell number when one is OBESE

Answer 36

Average weight person and obese person will have the same number of adipocytes, but an average person will have a higher microgram of triglycerides ? You can find this information by doing a biopsy and counting number of fat cells

Answer 37

Principles of Weight Control; - If total food calories exceed daily energy expenditure, excess calories Accumulate and store as Fat - The energy balance equation says body mass remains CONSTANT when Caloric intake EQUALS caloric expenditure - To unbalance the equation to produce weight loss: - Reduce caloric intake below daily energy requirements - Maintain caloric intake and increase energy expenditure, - Decrease daily calorie intake and Increase daily energy expenditure intake muscle be less than expenditure to lose weight

Answer 38

The First law of Thermodynamics -affirmed that Weight LOSS occurs whenever Energy output EXCEEDS energy intake , regardless of the diet's macronutrient mixture - A prudent dietary approach to weight loss reduces energy intake by 500 to 1000 kCal - Moderately reduced food intake produces Greater fat loss relative to the energy deficit than more severe energy restriction

Answer 39

Those who have controlled food, diet, will lose more weight than those who self-select and choose what they want to eat.

Answer 40

Percentage of total weight loss: Week 1: comprised of 70% water, 25% Fat, and 5%other You're mostly losing water week 2-3: 70% of Fat, 20% water and 10% other (you are primarily losing fat) Week 4: 85% fat, 15% protein (losing fat primarily) after 2 weeks, you are primarily losing fat and increasing protein loss

Answer 41

-The potential for successful long-term weight loss maintenance generally varies INVERSELY with the initial degree of fatness -reported that each year you gain 2 pounds. -For most individuals, initial success in weight loss relates POORLY to long-term success -participants in Supervised weight-loss programs (ex: weight watchers) lose about 8-12% of their original body mass -however, typically one to two-thirds of the lost weight returns within a year, and almost all of it within 5 years. most people do not maintain weight loss

Answer 42

Setpoint Theory: States that all persons (fat or thin) have a well-regulated internal control mechanism located deep within the lateral hypothalamus that maintains with relative ease a preset level of body weight and or body fat within a tight range -there is a comfortable weight that hypothalamus tries to maintain. -Exercise and FDA-approved antiobesity drugs may lower a person's set point, whereas dieting exerts NO effect -Each time body weight decreases below one's pre-established setpoint, internal adjustments that affect food intake and regulatory thermogenesis resist the change and conserve and or replenish body fat. (each time body weight drops, internal adjustments made to gain body fat) Theory NOT believed to be true (not well supported)

Answer 43

Biologic Feedback mechanism - when overfat people lose weight, adipocytes INCREASE their level of fat-storing enzyme LPL (facilitating body fat synthesis) and the Fatter the person before weight loss , the GREATER the LPL production with weight loss, - The Fatter one is at the start, the more vigorously the body attempts to regain the lost weight

Answer 44

Challenge to Setpoint proponents: -energy restriction produces a transient state of hypometabolism if the dieter maintains the state of negative energy intake (if you maintain that state, there will be new set point, you will still lose weight if maintain negative energy intake ) -This adaptive downregulation in resting metabolism does not persist when individuals lose weight but then reestablish balance where energy intake equals energy expenditure at their lower body weight.

Answer 45

Eating disorders: -Anorexia athletica: subclinical eating behaviors of athletes who fail to meet the criteria for a true eating disorder , but who exhibit at least One unhealthy method of weight control, including fasting, vomiting, or use of diet pills, laxative or diuretics (seen in wrestling athletes) - Anorexia nervosa: An Unhealthy physical and mental state characterized by a crippling obsession with body size and distorted body image (one can see ribs coming out, and still look at themselves and feel fat) - Bulimia Nervosa: purging and intense feelings of guilt and shame almost always follow the episodes of binge eating -Binge eating disorder: Individuals eat more rapidly than normal until they can consume no additional food.

Answer 46

Factors that affect weight loss (hydration level and duration of energy deficit) -Hydration level: 70% of the weight lost over the first week of energy deficit consists of water loss -Water loss progressively lessens while body fat loss increases from 25 to 75% -Restricting water during the first days of caloric deficit causes more total weight loss to occur, but the additional weight loss comes solely from water as dehydration progresses

Answer 47

Duration of energy deficit: -caloric equivalent of the weight lost increases as duration of caloric restriction progresses (longer you do exercise program, the more weight you lose overtime) -After 2 months, on a diet, the caloric equivalent of weight loss exceeds TWICE that in the first week. (staying on caloric restriction overtime has bigger effects long term)

Answer 48

Exercise for Weight control: -Excess weight gain often parallels Reduced physical activity, rather than increased caloric intake -An increased level of regular physical acitivity combined with dietary restraint maintains weight loss MORE Effectively than long-term caloric restriction alone A negative energy balance induced by increased caloric expenditure unbalances the energy balance equation for weight loss, improves physical fitness and health risk profile, and favorably alters body composition and body fat distribution for children and adults.

Answer 49

With Diet only: many people reduced body mass, fat mass, and fat free mass (losing weight) -with Diet and Exercise: you are reducing body mass, and fat mass and increasing Fat free mass (you gain weight , but it is fat-free mass; good) With Exercise only- you are increasing body mass, fat free mass and decrease fat mass.

Answer 50

Misconceptions about exercise 1. Increased physical activity increases food intake 2. Low Caloric stress of physical activity

Answer 51

Misconception 1: Increased physical activity increases food intake - Sedentary persons often do NOT balance energy intake and energy expenditure - Increased physical activity by overweight, sedentary individuals do NOT necessarily alter physiologic needs and automatically produce compensatory increases in food intake to balance additional energy expenditure

Answer 52

Misconception 2: Low caloric stress of physical activity - The calorie-expending effects of increased physical activity add up - The energy cost for various activities varies because of individuals differences in performance, style and technique; terrain, temperature, and wind resistance ; and intensity of participation

Answer 53

The recovery "Afterglow" - with low-to moderate exercise, the contribution of recovery metabolism to total energy expenditure remains small relative to exercise energy expenditure, ranging up to 75 kCal for exercise duration of 80 minutes - Exercise training induces faster adjustments in post-exercise energetics that reduce the magnitude of the total recovery oxygen consumption - *calories burned during physical activity represent the most important factor in total exercise energy expenditure, not calories expended during recovery

Answer 54

Resistance training positively affects muscular strength and FFM (fat free mass) during weight loss compared with programs that rely solely on food restriction - individuals who maintain high muscular strength levels tend to gain LESS weight than weaker counterparts - Standard resistance training performed regularly REDUCES coronary heart disease risk, improves glycemic control, favorably modifies the lipoprotein profile and Increases resting metabolic rate.

Answer 55

Dose-response relationship of energy expended -The Toal energy expended in physical activity relates in a Dose-response manner to the effectiveness of exercise for weight loss. -A reasonable goal progressively increases moderate exercise between 60 and 90 minutes daily (3-5x a week) -Focus on INCREASING DURATION not intensity for weight loss The energy cost of weight-bearing exercise relates directly to body mass; the overweight person expends considerably MORE Calories in such exercise than someone of average weight

Answer 56

Start Slowly and progress gradually - The initial stage of an exercise-weight loss program for a previously sedentary, overly fat person should be Developmental with moderate energy demands - The individuals should adopt long-term goals and personal discipline and restructure eating and exercise behaviors - Meaningful changes in body weight and body composition require at least 12 weeks.

Answer 57

-Combinations of increased physical activity and caloric restraint offer considerably MORE FLEXIBILITY for achieving a negative caloric imbalance than either exercise or diet alone -Dietary restraint plus increased physical activity through lifestyle changes offers health and weight loss benefits similar to those from combining dietary restraint and a vigorous program of structured exercise adding exercise to weight-control program facilities longer term maintenance of fat loss than total reliance on either food restriction or increased exercise alone. Combination of caloric restriction and exercise is MOST IDEAL.

Answer 58

American College of Sports Medicine recommends: - Adults participate in at least 150 min/Week of moderate-intensity physical activity - Overweight and obese individuals should participate in physical activity that approximates 250 to 300 min/week

Answer 59

Spot reduction: -States that an increase in a muscle's metabolic activity stimulates relatively greater fat mobilization form the adipose tissue in proximity to active muscle -for example, performing large numbers or sit-ups or side-bends will reduce excessive abdominal and hip fat -NO Research supports this -(you trigger fat burning, with increased heart rate, be in zone to sit up and side bends strengthen abdominal muscles.

Answer 60

Decreases in body fat reduce upper-body subcutaneous and deep abdominal fat rather than the more "resistant" fat depots in gluteal and femoral regions (pear shapes) -Men generally respond more FAVORABLY than women to effects of exercise on weight loss, which may be due to: -gender differences in body fat distribution -women many more effectively persevere energy balance with increased physical activity (keep essential fat stored) -Men often reduce energy intake with exercise training, whereas the depression of food intake with exercise may be LESS for women (women tend to eat more after exercise compared to men)

Answer 61

Increase the Lean, Not the fat - Endurance exercise training usually increases FFM (fat free mass) only slightly while muscular overlaid through resistance training increases muscle mass and strength (if you combine endurance training with resistance training, increase muscle mass/strength) - therefore, intense aerobic training should NOT coincide with resistance training to increase muscle mass - 1 year program of heavy resistance training for young ,athletic men increases body mass by about 20% - the rate of lean tissue gain rapidly plateaus as training progresses beyond the first year - For athletic women, first year gains in lean tissue mass average 50-75% of the absolute values for men.

Answer 62

Ideal combo for losing weight: | -aerobic training, resistance training and reduced caloric intake will help lose weight and maintain health