12.2 Body Composition Flashcards
What does body composition measure?
Proportion of fat mass vs lean mass on body
What type of body composition is more associated with health?
More lean mass and less fat mass
BMI considers body _____ and ______
height, weight. It is mass/height
What is percent body fat?
Expresses fat mass as a percentage of total mass
Which is better to determine body composition. BMI or percent body fat?
Percent body fat
Where is visceral fat located?
Fat mass that surrounds the internal organs
Where is subcutaneous fat located?
Right under the skin, above the abdominal muscles
Which fat is associated with a higher disease risk: visceral or subcutaneous fat?
visceral fat
What are the 2 best ways to determine body composition?
DEXA and Air/Water Displacement
How does DEXA work?
Dual X-ray absorptiometry uses low dose x-ray scan to scan the body in two planes
It gives an image used to determine body composition and also can indicate bone density
How does Air/Water Displacement work?
body mass/body volume (which you get from air/water displacement) = body density, which can imply body fat percentage.
What is a benefit and con of DEXA over displacement?
Very accurate, but more expensive
What are 2 older ways to determine body composition?
Measuring skin folds by pinching them and putting them in an equation. Prone to human error
Bioelectric Impedance - Electric current is sent through body and the resistance is measured (as fat is more resistant). However, can be influenced by hydration status.
What is the BMI useful for?
For population level data, ex Canada vs US
What is the main limitation of BMI?
Does not fully capture body composition
