CSSD Body Composition 3

Question 1

Which of the following BEST describes the concept of 'fat-free mass index' (FFMI) in the context of athlete assessment?

Accepted Answer

Fat-free mass divided by height squared

Answer

FFMI is calculated as fat-free mass (kg) ÷ height (m)², providing a height-adjusted measure of muscularity useful for comparing lean mass across athletes of different statures.

Question 2

An athlete's DXA scan shows a T-score of -2.6 at the lumbar spine. Which diagnosis applies, and what is the primary nutrition concern?

Accepted Answer

Osteoporosis; low bone mineral density increasing fracture risk

Answer

A T-score of ≤ -2.5 meets the WHO diagnostic threshold for osteoporosis, which significantly elevates stress fracture risk in athletes.

Question 3

When using hydrostatic weighing (underwater weighing) to estimate body density, what correction factor must always be applied?

Accepted Answer

Residual lung volume at the time of submersion

Answer

Residual volume — the air remaining in the lungs after maximal exhalation — creates buoyancy and must be measured or estimated to accurately calculate body density.

Question 4

A strength and conditioning coach asks the sports dietitian why two athletes with identical body weight and height have very different DXA-derived body fat percentages. The most likely explanation is:

Accepted Answer

Differences in fat distribution and lean mass between the two athletes

Answer

Body weight and height (and therefore BMI) do not capture differences in fat versus lean tissue distribution, so two athletes with the same BMI can have markedly different body fat percentages.

Question 5

The Jackson-Pollock 3-site skinfold equation for women uses which three sites?

Accepted Answer

Tricep, suprailiac, thigh

Answer

The Jackson-Pollock 3-site formula for females uses tricep, suprailiac, and thigh skinfolds, whereas the male version uses chest, abdomen, and thigh.

(CSSD) Board Certified Specialist in Sports Dietetics Practice Test

(CSSD) Board Certified Specialist in Sports Dietetics Practice Test

CSSD Body Composition 3