Lecture 6 Flashcards
weight management
What is the concept of body image
how we see our body in the mirror or in our mind and our satisfaction
what techniques are used to evaluate body weight
BMI
Hydrostatic weighing
bod pod
skin fold measurements, bioelectric impedance analysis (BIA)
dual energy x-ray absorptiometry
What are limitations of BMI
body composition, pattern of fat distribution, body fat
hydrostatic weighing
submerging in water, volume of water vs. weight, relatively accurate, requires trained technician and equipment
Importance of BMI
Provides an overall clue to a
person’s health, more accurate when combined with waist circumference measurements, population study
Bod Pod
measuring the volume of air displaced by an individual sitting, relatively accurate, expensive
Skin fold measurements
measuring the thickness of subcutaneous fat, accuracy best predicted by skill level of technician
Bioelectrical impedance analysis (BIA)
Measures resistance of electrical flow through body tissues
Sends weak electrical current
throughout the body, 3-4% error, inexpensive
may not work if too much water is consumed because water is a good electric current
Dual Energy x-ray absorbtimetry (DXA)
very low level x-ray to differentiate between bone, muscle, fat, most accurate
Energy balance
relationship between energy intake and expenditure (calories consumed vs. calories burned)
Factors that affect energy balance
physical activity, environment, physiological factors, social & individual psychology, food consumption or production
Physiological or genetic factors that influence our weight
body composition/type, thrifty gene, developmental factors
Thrifty Gene Theory
gene that store’s extra calories as weight (contributes to weight gain, hypothetical theory)
Set Point Theory
Body’s natural “set point”, weight that it tries to maintain
Characteristics of a healthy weight loss program
nutrition
physical activity
behaviour changing
monitoring food consumption
medical evaluation
better sleep
Anorexia Nervosa
self starvation, severe nutrient deficiency
Bulimia Nervosa
Reoccurring episodes of binge eating then purging
Binge eating
Binging, not followed by purging
What makes us gain/lose weight
energy balance, genetic/physiological factors, obesogenic environment
Risks of obesity
CVD, Type 2 diabetes, poor mental health, increase cancer risk
Percent contribution of fat
75% non genetic, 25% genetic
Android vs. gynoid obesity
Android: apple-shaped obesity
Gynoid: pear-shaped obesity
Factors that affect basal metabolism
higher lean body mass, greater height & weight, pregnancy, growth
Components of energy expenditure
BMR (60-70%) Basal Metabolic Rate
PA (20-35%) Physical activity
TEF (5-10%) Thermic Affect of food
