Chapter 10 – Body Composition
Learning Objectives
- What is body composition?
- How does body composition affect a person’s health?
- What are the health risks and costs associated with overweight and obesity?
- What is the significance of body fat distribution?
- What is Body Mass Index (BMI) and why is it important?
Terminology
- Body Composition: The measurement of the body’s proportion of fat mass to fat free mass.
- Fat Mass: The amount of fat tissue in the body often expressed as a percentage of total body mass.
- Fat Free Mass (FFM): not fat tissue in the body such as bones, muscles, ligaments, and blood.
- Essential Fat: the amount of fat needed for vital body functions.
- Non-essential fat: the amount of fat that exceeds the necessary fat needed for vital body functions. This fat is considered energy storage.
- Overweight: the accumulation of non-essential body fat to the point that it adversely affects health.
- Obesity: is characterized by excessive accumulation of body fat and can be defined as a more serious degree of being overweight.
- Adipose Tissue: another term for fat. More specifically it is loose connective tissue composed of adipocytes.
- Subcutaneous fat: fat tissue stored below the skin’s surface.
- Visceral Fat: fat tissue stored around central organs.
- Android shape: a body shape used to help characterize body fat distribution in which fat is stored in the abdominal region. The android shape is also called the “apple” shape.
- Gynoid shape: a body shape used to help characterize body fat distribution in which fat is stored in the hips, buttocks, and thighs. It is also called the pear shape.
- Body Mass Index (BMI): an index based on concept that weight and height should be proportionate. It is calculated by dividing weight by the height squared (weight/height2).
- Hydrodensitometry: This method attempts to measure the density of the body by using water displacement.
- Dual Energy X-ray Absorbtiometry (DEXA): A method of measuring body composition that uses low energy x-rays that also measure bone density.
- Air Displacement Plethysmography: A method of measuring body composition that measures the density of the body by using air displacement.
- Bio-electrical impedance analysis (BIA): A method of measuring body composition by emitting a small electrical current through the body and using the amount of resistance encountered by this current to predict body fat content.
- Skinfold Analysis: A method of measuring body composition by measuring the diameter of pinched skin at various sites on the body.
Chapter attribution to “Health and Fitness for Life” by Dawn Markell and Diane Peterson. Updating for a Canadian/North American context authored by Lynn Kabaroff
