Android apple shape refers to having most of the fat around the stomach and mid-section. Gynoid pear shape refers to having the fat stored around the hips.

A bigger number means more android and a smaller number means more gynoid. From a health risk standpoint, ideal values are believed to be less than 0. Fat Free Mass Index FFMI : The amount of mass that is not fat, relative to your height.

This includes muscle, bone, organs and connective tissue. It can be used to gauge relative muscle mass in lean individuals. Skeletal Muscle Mass SMM : An estimate of the total amount of skeletal muscle you have. Because muscle has approximately the same density as other organs liver, skin, etc… and other types of muscle heart, smooth muscle, etc… we are not able to directly the amount of skeletal muscle you have.

This is true of any commercially available body composition measurement bioelectrical impedance, underwater weighing. However, several scientific studies have been performed that demonstrate good accuracy between our estimated SMM and that measured by MRI or CT scanning.

Cut points in research are generally around 5. Cut points in research are generally around 0. Resting Metabolic Rate RMR : The number of calories the body needs to maintain its current mass under resting conditions.

The value provided by the DXA scan is estimated from the amounts of different tissues, and tissue specific metabolic rates. Bone Density: Shows how dense the bones are and can be used to assess the risk of osteopenia and osteoporosis. The z-score compares your bone density to what is normal for people similar in age and body size.

The t-score compares your bone density to that of a year-old. Anything higher than Between Anything under UC Davis Health School of Medicine Betty Irene Moore School of Nursing News Careers Giving.

menu icon Menu. Sports Medicine. Enter search words search icon Search × Enter search words DAX body composition analysis Sports Medicine UC DAvis Health. UC Davis Health Sports Medicine Learning Center Dual X-ray Absorptiometry. DXA body composition analysis. What does this scan show? DXA body composition analysis Dual X-ray Absorptiometry DXA is a quick and pain free scan that can tell you a lot about your body.

The body fat percentage is of most interest because it can be very helpful in assessing health. Because muscular tissue is denser that fat tissue, assessing ones body fat is necessary to determine the overall composition of the body, particularly when making health recommendations.

Two people at the same height and same body weight may have different health issues because they have a different body composition. Dual X-ray Absorptiometry DXA is a quick and pain free scan that can tell you a lot about your body.

Example analysis from a DXA scan PDF. Although body fat endures a negative reputation, fats and lipids play critical roles in the overall functioning of the body, such as in digestion and energy metabolism. Fat is the body's energy provider and energy reserve, which helps the body maintain a constant temperature.

Fats and lipids are also involved in the production and regulation of some hormones such as, steroid hormones. These are essential in regulating sexuality, reproduction, and development of the human sex organs, as well as in regulating the water balance in the body. Fats and lipids also have important structural roles in maintaining nerve impulse transmission, memory storage, and tissue structure.

Lipids are the major component of cell membranes. Fat serve as an energy reserve for the body, particularly as exercise progresses past 20 minutes.

From a performance stand point, excess body fat lowers your work to weight ratio, This means that a heavier person would consume more energy per minute of work resulting in a lower energy economy during activity.

In addition, excess body fat can lead to additional loads placed on joint during weight bearing activities such as running, causing joint distress. Healthy or athletic body fat percentages typically allow for more optimal performances, due to the improved economy and reduced injuries.

The immune system is often impaired when body fat stores are too low. A reduced ability to fight infections means more interruptions in training and more chance of being sick on race day. For female athletes, there are some very immediate consequences of a low body fat level, including a fall in circulating oestrogen levels.

This in turn can lead to a loss of bone mass, causing problems for women in later life through an increased risk of bone fracture. Assessing body fat can be done using the following methodologies: Hydrostatic weighing, skinfold assessment and bio-electrical impedance.

Of these methods, one that is both accurate and practical is skinfold measurement. The measurements are taken with calipers, which gauge the skinfold thickness in millimeters of areas where fat typically accumulates i.

Once the measurements are recorded, the numbers are inserted into an equation that calculates a body fat percentage and alternatively body lean mass. Skinfold is a preferred method of body fat measurement for non-clinical settings because it is easy to administer with proven accuracy and is not obtrusive with regards to the patient.