- Chapter 18 Body Composition and Nutrition for Health
EXERCISE PHYSIOLOGY
Lecture 3
-
- Body Composition
- Methods of Determining Body Composition
Metropolitan Life Insurance Company’s height/weight tables
Percentage above recommended weight
Body mass index (BMI)
Weight (kg) ? height (m2)
Problems with these methods
-
- No way to tell actual body composition
A very muscular person could be classified as obese
-
- Body Composition Measurement
Total body water
- _____________________
- _____________________
- Bone density
- _____________________
- Lean tissue mass
- Potassium-40
-
- Whole body density
- _____________________
- Thickness of various tissues
_____________________
- _____________________
_____________________
-
- Models of Body Composition
2-component
_____________________
-
- 3-component
_____________________
- _____________________
-
- 4-component
_____________________
- The 4-component model is the most accurate
-
- The 2-component Model
Underwater weighing
Based on body density
_____________________
-
- Use equation to convert body density to percent fat based on _____________________
-
- The 2-component Model
Skinfolds
_____________________
-
- Specific sites on the body based on _____________________
-
- Body density is calculated using specific equations
Percent body fat calculated from _____________________
-
- Underwater Weighing
Body Fatness for Health and Fitness
-
- Recommended body fat
Males
_____________________
- Females
_____________________
-
- Health concerns
_____________________
- _____________________
-
- Obesity
More evidence points to as a risk factor for CHD, and directly tied to two of major risk factors
Primary contributing factor: adult-onset diabetes, menstrual abnormalities, reproductive problems, heart size and function, arthritis, gout, and hypertension
Secondary contributing factor: endometrial carcinoma
- Diseases correlated with atherosclerotic disease, gallbladder disease, and death
Obesity
BMI of _____________________ as a classification of obesity
Prevalence of obesity in U.S. adults increased
15% in 1976-80
23.3% in 1988-94
_____________________ in 1999-2000
Include those classified as overweight
(BMI _____________________)
-
- Prevalence of overweight & obesity is _____________________
-
- Obesity
Prevalence of overweight in children and adolescents (ages 6-19)
5-7% in late 1970
11% in 1988-94
- _____________________ in 2000
Associated with an increase of type 2 diabetes
-
- Obesity Fat Cell Size vs. Number
25 billion fat cells in normal-weight individual
60-80 billion in obese individual
-
- During weight loss
Fat cell size _____________________, not fat cell number
-
- Severe obesity (fat mass _____________________)
Due to increase in fat cell number (_____________________)
-
- Less severe obesity
Due to increase in fat cell size (_____________________)
-
- Hyperplasia
Associated with greater difficulty losing weight and maintaining weight loss
Obesity Fat Cell Size and Number
-
- Obesity Genetic and Cultural Factors
Genetic factors
Account for about _____________________of the transmissible variance for fat mass and percent body fat
Cultural factors
Account for about _____________________
-
- Set Point Theory
The tendency of a person to return to a certain weight suggests that there is a biological set point for body weight, much like the set points for any negative feedback biological control system
-
- Set Point and Obesity
Physiological set point model
Biological signals provide input to hypothalamus
Food intake is either increased or decreased to maintain body weight
Cognitive set point model
Cognitive signals about perception of body weight
Influences food intake to maintain body weight
Physiological Set Point
Cognitive Set Point