Chapter 7 Understanding Body Composition Chaemarique George Britteni Davis
Did You Know? The body is composed of fat mass and fatfree mass. Fat is found in the organs (such as the brain, heart, liver, and lungs). A certain amount of fat is required for normal biological functions. This is referred to as essential fat.
What is Body Composition- the ratio between fat mass and fat-free mass. Amenorrheic- women who stop having a menstrual cycle. This affects women whose body fat drops below essential requirements such as gymnasts, ballerinas, long-distance runners, and anorexics.
A Big Difference Obesity Obesity is gender specific. Men- defined as body fat equal to or greater than 25 percent of total body weight. Women- equal to or greater than 32 percent of total body weight. Overweight Overweight refers to excessive weight for height without consideration of body comp. Overfat- a person carries a large proportion of body weight in the form of fat rather than lean tissue.
Nurturing Your Spirtuality Genetics is responsible for 25 to 40 percent of the factors that determine how fit we may have become. Genetics is responsible for 25 to 40 percent of the factors that lead to overweight and obesity. Our physical activity and eating habits determine whether genetic history becomes destiny. Healthy eating and sensible regular exercise are for a lifetime.
Regional Fat Distribution The waist-to-hip ratio (WHR) is a simple method for determining the distribution of body fat. Males: A WHR greater than 0.95 indicates an excessive amount of upper body fat. Females: A WHR greater than 0.80 indicates an excessive amount of upper body.
Methods for Measuring Body-Weight Status Height/Weight Tables Body Mass Index
Height/Weight Tables Height/weight tables act as a standard for total body weight based on height and gender without regard to the composition of weight. Height/weight tables do not measure body composition. Act as a standard for total body weight based on height and gender. These tables are poor criteria for the establishment of weight-loss recommendations.
Body mass index (BMI) is not everyone s favorite number. It provides an acceptable estimate of the proportion of our body weight that s composed of fat. BMI( body mass index) is the ratio of body weight in kilograms to height in meters squared. Although BMI does not provide an estimate of percent body fat, it s far more accurate than height/weight tables. Body Mass Index
Just To Let You Know Your ideal weight, if there is such a thing, depends on a host of factors: Gender Age Height Frame Size
Underwater Weight The loss of weight in water is directly proportional to the volume of the body that displaces that water. The density of bone and muscle is higher than that of water and tends to sink. People with more muscle mass weigh more in water than do those who has less.
More Underwater.. Underwater weighing has an inherent error of measurement that can be minimized when the residual volume of air is accurately measured. The equipment required for underwater weighting includes an autopsy scale with a capacity of approximately 9 kg (about 20 pounds). The scale is suspended over a tank of water at least 4 feet deep.
Bioelectrical Impedance Analysis BIA is a relatively new and simple method of determining body composition. It has a current that passes thru the body of the person being measured via electrodes. Water is an excellent conductor of electricity, fat only contain 14 to 22 percent of water and it resists to electrical flow.
Skinfold Measurements One of the least expensive and most economical methods of measuring body composition. When performed by skilled technicians, skin fold measurements correlate well
Dual Energy X-Ray Absorptiometry DEXA was developed to measure bone mineral density, but advances in technology have allowed for the qualification of fat and lean tissue as well. It uses an X-Ray generator and two energy levels as a source of radiation. This system allows for simultaneous measurement of bone mineral, fat, and nonbone lean tissue.