Fat-Free Mass PDF
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This document covers the concepts of fat-free mass and fat mass, along with related factors like energy expenditure, hormones, and genetics. It also explores metabolic processes involved in weight regulation and offers insight into relevant strategies for weight management.
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Fat-Free Mass Total body mass excluding fat tissue. Organs (Skin, hair, nails), Bones, Minerals, Lean body mass (muscle) Fat Mass Total body mass that is fat tissue. Consists of storage (essential, visceral ), & brown and white adipose tissue. Fat Free mass v. Fat Mass in Males and Females subcuta...
Fat-Free Mass Total body mass excluding fat tissue. Organs (Skin, hair, nails), Bones, Minerals, Lean body mass (muscle) Fat Mass Total body mass that is fat tissue. Consists of storage (essential, visceral ), & brown and white adipose tissue. Fat Free mass v. Fat Mass in Males and Females subcutaneous fat Fat mass under the skin near the abdominal area. Storage fat. Visceral fat fat mass located around major organs; part of storage fat White adipose tissue promotes energy storage brown adipose tissue burns energy over storing it. Mainly in babies. The brown color is a result of the mitochondria Helps w/weight loss and the reduction of obesity Adipocyte Hyperplasia Increase in the number of fat cells. *fat cells decrease, but do not disappear via weight loss Adipocyte Hypertrophy Increase in the size of fat cells.*fat cells shrink, but do not disappear via weight loss What are the components of total energy expenditure Exercise, NEAT, Thermogenesis, RMR Body Weight Regulation Balance of energy intake and expenditure. Energy intake - the macronutrient profiles Body weight regulation CHO 4 Fat 9 Protein 4 Alcohol 7 contribute to total caloric intake, with specific caloric values per gram. RMR (resting metabolic rate) Body weight regulation Calories burned at rest while sleeping. Most variable component - AT: structured planned physical activity (activity thermogenesis): fidgeting, walking, non structured activity influenced by factors such as age, sex, and body composition. activity thermogenesis (AT) nonexercise activity thermogenesis (NEAT), the energy expended during activities of daily living, and the energy expended during sports or fitness exercise. TEF (thermic effect of food) Body weight regulation Increase in energy expenditure associated with the consumption, digestion, and absorption of food NEAT non-exercise activity thermogenesis. Energy expended during activities of daily living, and the energy expended during sports or fitness exercise. How genetics impacts body weight regulation - Size and # of fat cells- genetically determined Regional distribution of body fat - RMR -Set point theory: theory (not proven) theorize bodies genetically want to be at a certain body weight or vise versa -Epigenetics: interaction between our genes and the environment and whether or not they're expressed How Inflammation impacts weight regulation Insulin resistance: promotes fat storage if excess amounts of calories are eaten, insulin resistance promotes fat storage, helps promote muscle protein synthesis Muscle protein loss: more inflammation means more loss of muscle Leptin resistance: Inflammation can cause elevated levels of leptin due to increased fat tissue and stress on the body. However, when leptin signaling is disrupted, the brain doesn't respond to these higher levels, leading to the body not recognizing when it's full. Set Point Theory Body's genetically preferred weight range. Epigenetics Gene-environment interaction affecting gene expression. Insulin Resistance Reduced sensitivity to insulin, promoting fat storage. Leptin Resistance Impaired response to hormone regulating hunger. Factors Affecting Body Weight (5) Sleep deprivation Genetic influences Obesogens Inflammation Behavioral Factors Sleep Deprivation Lack of sleep: increases ghrelin (hunger hormone) Decreases leptin (satiety hormone), leading to increased caloric intake because of cravings for CHO food How does gene expression affect body weight? Genetics can determine the number and size of fat cells, as well as regional fat distribution. How does insulin resistance affect body weight? (5) Defective glucose disposal system and a depressed level of thermogenesis. The greater the insulin resistance, the lower the thermic effect of food = increased fat storage = Increased hunger and appetite =decreased energy expenditure = increased fat cell size = changes in fat cell distribution How do obsenogens affect body weight? Disruption of lipid metabolism → favor/promote fat storage by altering gene expression and disrupting hunger/appetite regulation hormones Cholecystokinin Produced: In small intestine (approx 15 min after a meal) primarily stimulated by protein and fat Action: Suppression of gastric emptying, decreases feeling of hunger, resulting in reduced food intake Leptin Produced by white adipose cells (mainly white subcutaneous fat) stimulated by the release of insulin Action: Lessens hunger/appetite blocking the production of neuropeptide Y; INC production of hormones that keep hunger levels in check, increase metabolism Insulin Produced in the pancreas in response to the rise of of blood glucose levels following the consumption of food Action: reduces hunger, in part by stimulating the production of leptin Ghrelin A hunger-arousing hormone secreted in stomach Action: Increases appetite and hunger (levels rise before eating and fall after a meal) Glucagon-like peptide-1 Produced in small intestine, prompted by food intake Action: Increases satiety, slows gastric emptying, and stimulation of metabolism Pancreatic peptide YY Produced in ileum and colon following food consumption Function: delays digestion, allows for longer periods of satiety and curbs appetite by binding to receptors of the brain Trillodothyronine Produced in thyroid gland, triggered by thyroid stimulating hormone regulates the metabolism Cortisol Produced in adrenal cortex; regulates metabolism and stimulates appetite Medical complications of obesity Health Risks: -pulmonary disease -nonalcoholic fatty liver disease -gallbladder disease - gynecologic abnormalities -osteoarthritis -skin issues -gout -phlebitis -cancer -severe pancreatitis -hypertension -dyslipidemia -diabetes -coronary heart diease -cataracts -stroke -hypertension Metabolic Syndrome risk factors (5) Waist circumference Men: > 40 inches Women: > 35 inches Serum TG: ≥ 150 mg/dl HDL Men: < 40 mg/dl Women: < 50 mg/dl Blood pressure: ≥ 135/85 mm Hg Fasting blood glucose: ≥ 100 mg/dl ***3 or more = metabolic syndrome Metabolic syndrome Waist Circumference Criteria Men: > 40 inches, Women: > 35 inches. Metabolic syndrome Serum TG ≥ 150 mg/dl Metabolic Syndrome HDL Men: < 40 mg/dl Women: < 50 mg/dl Metabolic syndrome blood pressure ≥ 135/85 mm Hg Metabolic Syndrome Fasting blood glucose ≥ 100 mg/dl Rapid weight loss results in - Higher protein losses - Sharp decrease in RMR -Cons: not sustainable, mostly water weight, nutrient deficiencies, affects hormone levels metabolism slows down- sharper dec in resting metabolic rate =harder to lose weight, easier to regain it If losing weight to quickly you're losing muscle mass Weight loss recommendations - the more body fat a person has the more fat they can lose each week Weight Loss Recommendation for BMI 27-35 0.5 - 1 lb/week safe weight loss. Goal: 10% reduction in 6 months Weight Loss Recommendation for BMI > 35 1-2 lbs/week safe weight loss. Goal: 10% reduction in 6 months weight loss strategies (6) 1-Lifestyle/behavior modification 2-Diet modification 3-Increased physical activity (recommend these 3 things first & if PT tries things listed below the 3 should still be practiced) 4-Pharmacotherapy 5-Surgery 6-Weight maintenance weight loss strategies Goal setting Stimulus Control Problem Solving Cognitive Restructuring Self-monitoring Relapse prevention What level of confidence should someone have when goal setting? (75% confident they can achieve goal) otherwise modify Name all the weight loss strategies Goal setting Stimulus control Problem solving Self monitoring Relapse prevention Energy-restricted diet Meal replacement programs Commercial programs Very low calorie diets Stimulus Control ID stimuli encourage eating and limit exposure -Use food record, feelings associated to when they eat, 5 W's problem solving Weight loss strategies Define problem, generate solutions, implement, and evaluate Cognitive Restructuring identify negative thoughts weight loss strategies - Self monitoring Food and PA (physical activity) records, blood sugar glucose, caloric intake, weighing self Weight Loss Strategies - Relapse Prevention Anticipate (potential relapses) and plan coping strategies Energy-Restricted Diet What is the kcal deficit range? General advice for someone who is on the diet 500-1000 kcal deficit for weight loss. INC fiber, DEC alcohol and sugar 1.2 g/kg/d protein - to preserve lean body mass Multivitamin Vitamin Therapy recommended if below