Essential Fat Essential fat • ~3% of body mass • Consists of fat stored in: – – – – – – – – –
Marrow of bones Heart Lungs Liver Spleen Kidneys Intestines Muscles Lipid-rich tissues of the central nervous system
Sex-specific fat (Females) • ~9% 9% off body b d mass • Essential for childbearing and other hormonerelated functions In essence, what represents the minimal fat percentage necessary for healthy female function?
Menstrual Cycle y Disturbances • Common among athletic females, especially i ll whom? h ? – Athletes who need low-weight to do well – Athletes hl who h need d to “look “l k good” d” to do d wellll
Skinfold Measurements • The rationale for using g skinfolds to estimate total body fat comes from the p between close relationship – Subcutaneous fat – Internal fat – Whole-body density
Skinfold Measurements ((cont’d)) • The sum of several skinfolds reflects – Amount of subcutaneous fat – An estimate of total body fat – An estimate of body density
• Are useful measurements for describing regional distribution of fat
Bioelectrical Impedance Analysis (BIA) • A small, alternating current flowing between two electrodes – Passes more rapidly through hydrated fat-free body tissues and extracellular water – Passes more slowly through fat or bone
Regional Distribution of Body Fat (cont’d) • Elevations in AVF volume – increased risk for developing CVD – increased risk of getting type 2 diabetes – increased chances of metabolic syndrome
“Most Most obese persons will not stay in treatment. Of those who stay in treatment most will not lose weight, treatment, weight and of those who do lose weight, most will regain it. it ” Dr. Albert Stunkard Obesity Specialist at Penn
Dieting g •Ap prudent dietaryy approach pp to weight g loss unbalances the energy balance equation – Reduce daily energy intake to 500 to 1000 kCal below the daily energy expenditure
Setpoint p Theoryy • Argues g that p people p have a well-regulated g internal control mechanism • Control center – may be located in the lateral hypothalamus – possibly within the fat cells themselves
Low carbohydrate-ketogenic y g diets The South Beach Diet High protein diets High-protein What are the Semistarvation diets pros and cons p Well-balanced diets to all of these?
Exercise and Weight g Loss (cont’d) ( ) • Total energy gy expended p in physical p y activityy follows a dose-response relationship – Adjust volume – Adjust intensity – Adjust frequency
