Quiz 11 - Unit 11: Body Composition

Body mass index (BMI) is used to assess: a. overall body composition b. body fat percentage c. fitness level d. relative weight to height ratio and as a predictor of future disease risk e. none of the above

Body mass index (BMI) describes relative weight for height. BMI is often used as a predictor of future disease risk. However, one can be overweight and not be obese. Overweight refers to an excess of an amount of weight that includes all tissues: bone, muscle, water, and fat. Obesity refers specifically to body fat. The National Heart, Lung, and Blood Institute (NHLBI) recommends that BMI is used to assess overweight and obesity and not to monitor changes in body weight. According to an expert panel formed in 1998 by the NHLBI, BMI is the key preferred measure to be used in clinical guidelines for the identification, evaluation and treatment of overweight and obesity in adults.

Bioelectrical impedance analysis (BIA) is one method to determine body composition. a. True b. False

Numerous methods are used to determine body composition. Body composition measurement is an important part of the initial assessment procedure for new clients and an important ongoing evaluative test for existing clients. (Excessive levels of body fat are associated with cardiovascular disease, cancer, and other maladies.) Body composition assessment is also an important source of motivation for clients because it demonstrates (hopefully) positive changes in overall fitness levels. The fat and lean compartments of the human body can be determined through the following methods. Bioelectrical impedance (BIA): BIA devices were developed on the basis that water conducts electricity better then fat. Because muscle has a high water content and fat has a very low water content, the rate at which your body conducts electricity can be used to estimate body fat analysis. A small portable instrument applies an electrical current to an extremity and resistance to that current is measured. Total body water is calculated and the value can be used to estimate percent body fatness. Many BIA devices have been developed; there are even handheld versions. Many are extremely expensive. Keep in mind that BIA devices were developed mostly for the population at large and use calculations and norms for the average person. In addition, recent scientific reviews of these methods indicate that they are unreliable.

Ectomorphs are classified as: a. Muscular body types b. Slim or linear body types c. Round types d. None of the above

The way your body looks is a result of your genetics and environmental factors (such as training and nutrition). The genetic factor has a dominant influence on your body structure, both inside and out. Scientist W. H. Sheldon devised a system of classifying different human body types. He termed this system somatotype. Using this system, humans can be classified into three body types: a. Mesomorphic, or muscular b. Ectomorphic, or slim and linear c. Endomorphic, or fat and round

All of the following are methods to assess body composition except: a. DEXA b. Body mass index (BMI) c. Skinfold thickness d. Hydrostatic weighing e. Bioelectrical impedance (BIA)

Since body weight (and not percent body fat) is solely used in determining BMI, it may not be the best way to assess those who have a larger percentage of muscle (such as body builders) or who have an athletic body type. Because muscle weighs more than fat, those who have well-developed muscles typically appear overweight or obese according to the BMI reference chart. We do not recommend using BMI as the only method to assess your body composition for those with an athletic or muscular build. An estimation of body fat using a skinfold (BIA) device is more accurate.

When taking skinfold measurement readings, only one attempt per site is recommended for an accurate reading. a. True b. False

Skinfold Measurement Tips: 1) When taking measurements, do so directly on the skin, not through the clothes. Readings should be taken in a standing position and on one side of the body—usually the right side. 2) Take readings 3 times and use the average of the two closest readings for use in the appropriate formula. 3) Practice, practice again, and keep practicing. Measurements are more reliable with more experience, so practice is crucial to accuracy.

The body is composed of lean body mass (LBM) and body fat. a. True b. False

The three major structural components of the human body include muscle, bone, and fat. These components are categorized as lean body mass (LBM) and total body fat. Muscle and bone comprise the body's LBM, while different types of fat account for total body fat.

Endomorphs are slim body types. a. True b. False

The way your body looks is a result of your genetics and environmental factors (such as training and nutrition). The genetic factor has a dominant influence on your body structure, both inside and out. Scientist W. H. Sheldon devised a system of classifying different human body types. He termed this system somatotype. Using this system, humans can be classified into three body types: a. Mesomorphic, or muscular b. Ectomorphic, or slim and linear c. Endomorphic, or fat and round

The somatotype system classifies the human body into how many categories? a. 1 b. 2 c. 3 d. 4 e. None of the above

The way your body looks is a result of your genetics and environmental factors (such as training and nutrition). The genetic factor has a dominant influence on your body structure, both inside and out. Scientist W. H. Sheldon devised a system of classifying different human body types. He termed this system somatotype. Using this system, humans can be classified into three body types: a. Mesomorphic, or muscular b. Ectomorphic, or slim and linear c. Endomorphic, or fat and round