How TO: Body Composition
​(body fat % measurement)

Gathering body composition statistics provides a measure of a your starting point and progression. Repeated measurements of weight, skinfold thicknesses, circumferences, and body mass index can help track the changes in your body composition (decreasing body fat, increasing lean body mass) and may be a good indication of the effectiveness of your program.
Body fat can be measured in a variety of ways. The choice of method depends on available tools and expertise. It is important to understand that the BF% measurement at face value is not of the utmost importance. It is the degree in change from one measurement to the next that should be the focus.  Each method has various degrees of accuracy, and has multiple variables that can change each reading.  It is recommended you measure your body composition the same way, at the same time, under the same conditions (food/water intake), so that each of your readings can be as parallel and comparable as possible.  The goal is to have achieve a desired change in BF%, and to reach/maintain healthy levels. 

​Bioelectrical impedance ​(Recommended)

Bioelectrical Impedance DeviceBioelectrical Impedance Device
If you have a gym membership, most gyms make this tool easily accessible to its members. Simply ask a staff member! 

Bioelectrical impedance involves using a portable instrument to conduct a minute electrical current through the body in order to estimate fat percentages. This method is based on the hypothesis that tissues high in water content conduct electrical currents with less resistance than those with little water content (such as adipose tissue).  As such, this method is highly sensitive to water content of the tissues and body. Take readings before and after a workout to see how much the results can change.

​Skinfold calipers

CalipersSkinfolds Calipers
If you or your gym does not have a BIA Device, skinfold calipers are the next easiest/economical option to measure body composition.  Skinfold calipers are used to measure the thickness of subcutaneous fat (the fat beneath the skin) at specific anatomical sites. This method requires measuring the thickness of a double layer of skin and the underlying fat. 
There are numerous equations for determining body fat percentage from skinfold thickness.  COSFLEX trainers use the Durnin-Womersley formula. If using calipers for your check in, simply type in the measurements in the spaces provided on the check in form and your trainer will calculate your body composition and update your profile page with the results. 
INSTRUCTIONS: Refer to each image and read the caption.  Take skinfold measurements on the right side of the body. Recommended to take these measurements first thing in the morning, before eating/drinking. Remember the goal is to take your measurements the same way at the same time under the same conditions every time.  
Biceps Skinfold
Biceps skinfold: A vertical fold on the front of the right arm over the biceps muscle, halfway between the shoulder and the elbow.
Triceps Skinfold
Triceps skinfold: A vertical fold on the back of the upper arm, with the arm relaxed and held freely at the side. This skinfold should also be taken halfway between the shoulder and the elbow. The midpoint is easiest to find with the arm flexed.
Subscapular skinfold
Subscapular skinfold: A 45-degree angle fold of 1-2 cm, below the inferior angle of the scapula .
Iliac Crest Skinfold
Iliact Crest Skinfold: A 45 degree angle fold, taken just above the iliac crest at the anterior axillary line

Hydrostatic/Underwater Weighing

Underwater weighing is a method of determining the proportion of fat to lean tissue based. The procedure compares the difference between dry, land weight with underwater weight, correcting for air in the lungs and water density. Lean tissue is denser than fat, so the leaner person will weigh more underwater and sink more. Those with more fat sink less. The results of underwater weighing determine a person’s overall density compared to the water and are a ratio of body weight to body volume.

DEXA

A Dual-Energy X-Ray Absorptiometry scan measures bone mineral density alongside body composition. Participants lie on a table while a machine passes over their body. measuring the absorption of x-ray beams into parts of the body, technicians can calculate bone mineral density, lean body mass and fat mass.​

Air Displacement 

Similar to underwater weighting, Air Displacement machines, like "Bod Pods" measure air displacement by the individual, and technicians can determine body density. Like underwater weighing, the participant’s body density is then used to calculate body composition.