Review Supplement Info Waist-to hip Ratio, Gurth Measurements & Skin Fold

Transcription

1 THIS MATERIAL IS A SUPPLEMENTAL TOOL. IT IS NOT INTENDED TO REPLACE INFORMATION PROVIDED IN YOUR TEXT AND/OR STUDENT HAND-BOOKS. Assessing Percent Body Fat: While hydrostatic weighing and the Bod Pod are considered more accurate, measuring skin folds is a less expensive and fairly reliable way to measure body composition in the field. 1) Waist Circumference and Waist-to-hip ratio Your waist circumference indicates how much fat is collected around your midsection. Doctors aren't sure why, but fat around your middle (called central obesity) is more dangerous than fat around other parts of the body, like your hips. People who have a high waist circumference and a high waist-to-hip ratio are more at risk for many diseases associated with being overweight, particularly heart disease and diabetes. To measure your waist-to-hip ratio: 1. Client stands with feet together, arms at side 2. Measure is at clients side 3. With client s abdomen relaxed, place the tape measure around the narrowest part of the torso, between the umbilicus and the bottom of the sternum (use belly button as mark); keeping tape tight, but not puckering skin 4. Keep the tape measure parallel to the ground 5. Record to nearest 0.1 cm 6. Measure squats at client s side and places tape measure around the client s buttocks were it has the greatest size 7. Keep the tape in the horizontal plane, and measure to the nearest 0.1 cm 8. Dived the waist measurement by the hip measurement Women with values above 0.86 and Men with values above 0.95 are at a higher risk of disease. Waist-to-hip Ratio Waist Circumference To measure your waist circumference: Wrap a tape measure around your middle at the level of your belly button. The risk of heart disease and diabetes increases if your waist circumference is more than 35 inches (88 cm) for a woman and more than 40 inches (102 cm) for a man. You should strive for a waist size less than 31.5 inches if you are a woman and less than 37 inches if you are a man. 6/4/2016 1

2 2) Girth Measurements (Checklists in Workbook & instructions in text pg 168) Anthropometric Measurements: REQUIRED!! An inexpensive and effective way to track your client s progress is to measure circumferences of various areas of the body. Taking circumference (girth) measurements: 1. Have the subject stand tall and relaxed, feet hip width apart. 2. Stand to the side of the subject, not in front of them. 3. Always take the measurements on the same side of the body (usually right side, or alternatively the subject s dominant side). 4. Hold the tape firmly, and pull it snugly, but not tight. 5. Check to see that the tape is parallel to the floor. 6. Strive to use site markers consistently, to ensure accurate comparisons of future measurements. Site Marker Inches (to nearest 1/4 inch) Neck Shoulders At mid-neck At the prominence of the deltoid muscle, across both shoulders Chest Forearm At the nipple line, under the arms and across the back At widest part between elbow and wrist Upper Arm At the prominence of the biceps Waist Abdomen (women) Hips Thigh (upper) Thigh (quadriceps) At the narrowest part of the trunk below the rib cage At the largest point below the navel, above the hips. At the prominence of the gluteal muscles Just below the gluteal fold At the prominence of the quadriceps Calf At the widest circumference 6/4/2016 2

3 Chest Girth Aim: To measure the circumference of the chest, as a measure of the chest muscles and lung size. Equipment required: flexible metal tape measure and pen suitable for marking the skin. If a plastic or cloth tape is used, it should be checked regularly against a metal tape as they may stretch over time. Description / procedure: This measure is taken at the level of the middle of the sternum (breastbone), with the tape passing under the arms. After the tape is in position, the arms should be relaxed by the side, and the measurement taken at the end of a normal expiration. When recording, you need to make sure the tape is not too tight or too loose, is lying flat on the skin, and is horizontal, particularly around the back. Reliability: Factors that may affect reliability include changes to the testing personnel, constant and even tension on the tape, and correct land marking (finding the correct anatomical site for measurement). Advantages: low costs involved in the testing procedure. Waist or Abdominal Girth Aim: the purpose of determining waist girth is to gain a measure of the amount of abdominal fat (visceral fat), which has been linked to increased risk of coronary heart disease and diabetes. Equipment required: flexible metal tape measure and pen for marking the skin. If a plastic or cloth tape is used, it should be checked regularly against a metal tape as others may stretch over time. Description / Procedure: The waist measurement is taken at the narrowest waist level, or if this is not apparent, at the mid point between the lowest rib and the top of the hip bone (iliac crest). When recording, you need to make sure the tape is not too tight or too loose, is lying flat on the skin, and is horizontal. Validity: The health risk may not be accurate in those individuals with thick waist musculature or those that are particularly tall or short. For women who deposit fat primarily lower on the body (hips, buttocks, and thighs), waist measurements in isolation are have a poor relationship with health factors. Reliability: Factors that may affect reliability include changes to the testing personnel, constant and even tension on the tape, and correct land marking (finding the correct anatomical site for measurement). Comments: Clothing over the site should be removed if possible to make sure measuring tape is positioned correctly and that the correct circumference is determined. Girth measurements combined with skin fold measurements can give a clearer picture of changes in tissue composition and distribution of muscle and fat. For this girth measurement, due to the location of the measure, care should be taken to maintain personal privacy of the subject, and sometimes it is appropriate to measure over clothing. If so, this should be recorded with the results. Advantages: low costs involved in the testing procedure, and ease of self testing Comments: Clothing over the site should be removed if possible to make sure measuring tape is positioned correctly and that the correct circumference is determined. Girth measurements combined with skin fold measurements can give a clearer picture of changes in tissue composition and distribution of muscle and fat. 6/4/2016 3

4 Hip Girth Aim: to measure the circumference of the hip area, as a measure of the underlying hip structure, musculature and adipose tissue. When combined with the measure of abdominal girth in the Waist-Hip Ratio (WHR), has been shown to be related to the risk of coronary heart disease Equipment required: flexible metal tape measure and pen suitable for marking the skin. If a plastic or cloth tape is used, it should be checked regularly against a metal tape as they may stretch over time. Description / procedure: The hip girth measurement is taken over minimal clothing, at the level of the greatest protrusion of the gluteal (buttock) muscles. The subject stands erect with their weight evenly distributed on both feet and legs slightly parted, making sure not tense the gluteal muscles. When recording, you need to make sure the tape is not too tight or too loose, is lying flat and is horizontal. It may help to have the subject stand on a box to make the measurement easier. Reliability: Factors that may affect reliability include changes to the testing personnel, constant and even tension on the tape, and correct land marking (finding the correct anatomical site for measurement). Advantages: low costs involved in the testing procedure, and ease of self testing Comments: Clothing over the site should be removed if possible to make sure measuring tape is positioned correctly and that the correct circumference is determined. Girth measurements combined with skin fold measurements can give a clearer picture of changes in tissue composition and distribution of muscle and fat. For this girth measurement, due to the location of the measure, care should be taken to maintain personal privacy of the subject, and sometimes it is appropriate to measure over clothing. If so, this should be recorded with the results. 6/4/2016 4

5 Arm Relaxed Girth Aim: To measure the circumference of the arm, as a measure of the underlying musculature and adipose tissue. Girth measurements combined with skin fold measurements can give a clearer picture of changes in tissue composition and distribution of muscle and fat. Equipment required: flexible metal tape measure and pen suitable for marking the skin. If a plastic or cloth tape is used, it should be checked regularly against a metal tape as they may stretch over time. Description / procedure: First mark the site to be measured. This girth measurement is usually taken on the right side of the body. The arm is relaxed and hanging by the side, and the circumference is taken at the level of the mid-point between the acromial (boney point of shoulder) and the olecranon (boney point of elbow) processes. When recording, you need to make sure the tape is not too tight or too loose, is lying flat on the skin, and is horizontal. Reliability: Factors that may affect reliability include changes to the testing personnel, constant and even tension on the tape, and correct land marking (finding the correct anatomical site for measurement). Advantages: low costs involved in the testing procedure Comments: Clothing over the site should be removed if possible to make sure measuring tape is positioned correctly and that the correct circumference is determined. 3) Skin fold Measurements (Checklists in Workbook & instructions in text p, ) Technique for Pinching the Skinfold: 1. Place fingers perpendicular to skinfold, about 1 cm from site. 2. Firmly pinch the skinfold between the thumb and two fingers, and lift away from underlying tissues. 3. Place the jaws of the caliper perpendicular to the skinfold at the measurement site. Maintain the finger pinch while taking the measurement. 4. Read the measurement 1 to 2 seconds after the jaws contact the skin. 5. Wait 15 seconds before taking a second measurement at the same site. If the measurement varies by more than 1 to 2 mm, take it again. 6/4/2016 5

6 Description / Procedure: Estimation of body fat by skin fold thickness measurement. Measurement can use from 3 to 9 different standard anatomical sites around the body. The right side is usually only measured (for consistency). The tester pinches the skin at the appropriate site to raise a double layer of skin and the underlying adipose tissue, but not the muscle. The calipers are then applied 1 cm below and at right angles to the pinch, and a reading in millimeters (mm) taken two seconds later. The mean of two measurements should be taken. If the two measurements differ greatly, a third should then be done, then the median value taken. The Sites: there are many common sites at which the skin fold pinch can be taken. For a description and photographs of these sites go here. Results: Because of the increased errors involved, it is usually not appropriate to convert skin fold measures to percentage body fat (%BF). It is best to use the sum of several sites to monitor and compare body fat measures. In order to satisfy those who want to calculate a percentage body fat measure, there is a sample of equations for calculating this here. Below is a table of general guidelines for using total sum (in millimeters) of the seven main skin fold sites (tricep, bicep, subscap, supraspinale, abdominal, thigh, calf) Equipment Required: skin fold calipers (e.g. Harpenden, Holtain, Slimglide, Lange). These should be calibrated for correct jaw tension and gap width. Target Population: suitable for all populations, though it is sometimes difficult to get reliable measurements with obese people. Validity: using skin fold measurements is not a valid predictor of percent body fat; however they can be used as a monitoring device to indicate changes in body composition over time. It is important to maintain correct calibration of the calipers (more about calibrating calipers) Reliability: the reliability of skin fold measurements can vary from tester to tester depending on their skill and experience. There are accreditation courses available through ISAK. Advantages: Skin fold measurements are widely utilized to assess body composition. It is a lot simpler than hydrostatic weighing and many of the other body composition techniques. After the original outlay for calipers, the daily tests costs are minimal. Other Considerations: some subjects may feel uncomfortable stripping down in front of the tester; therefore every effect should be made to make them feel comfortable. For legal reasons, it is wise to have another person present, and to have female s testers for female subjects. The right side measurement is standard, though in some situations you may need to test someone on the left side. If so, you must record this and endeavor to always test on the same side for that person. Reasons for testing on the left side may include injuries, amputation, deformities, or other medical conditions. 6/4/2016 6

7 Tricep Skin fold Landmark: At the level of the mid-point between the acromiale (lateral edge of the acromial process, e.g. bony tip of shoulder) and the radiale (proximal and lateral border of the radius bone, approximately the elbow joint), on the mid-line of the posterior (back) surface of the arm (over the triceps muscle). Abdominal Skin fold Landmark: 5 cm adjacent to the umbilicus (belly-button), to the right side. Pinch: The arm should be relaxed with the palm of the hand facing forwards. A vertical pinch, parallel to the long axis of the arm, is made at the landmark. Pinch: The vertical pinch is made Supraspinale Skin fold Landmark: The intersection of a line joining the spinal (front part of iliac crest) and the anterior (front) part of the axilla (armpit), and a horizontal line at the level of the iliac crest. Front Thigh Skin fold Landmark: The midpoint of the anterior (front) surface of the thigh, midway between patella (knee cap) and inguinal fold (crease at top of thigh). Pinch: The pinch is directed medially (towards the centerline) and downward, following the natural fold of the skin (at an approximate angle of 45 degrees) Pinch: A vertical pinch. 6/4/2016 7

8 SAMPLE Step 1 Understand that there are a number of different skinfold calipers available on the market--some fairly cheap and some very expensive. When purchasing skinfold calipers, you get what you pay for. For home use, you can buy them for as little as $10. The calipers used in professional laboratories and universities can cost several hundred dollars. The most important element in achieving accurate skinfold measurements is practice and the correct anatomical locations. Use the directions below, as well as the material accompanying the calipers you buy and practice. Step 2 Take the following nine measurements, for men and women: 1) Bicep (vertical skin fold measurement on the bicep halfway between the shoulder and the forearm); 2) Triceps (vertical measurement right below where the triceps horseshoes); 3) Chest (vertical measurement at the top middle of the chest,below the collar bone; 4) Back (vertical pinch the skin between the scapula and spine; 5) Abdomen (vertical skin fold measurement to the right of the belly button; 6) Lower Back (horizontal measurement between the kidney and the spine; 7) Quadriceps (vertical measurement halfway up the quadriceps; 8) Calve (horizontal measurement at the top middle of the calve; and 9) Hip (horizontal measurement on the hip). Step 3 Open and apply skinfold calipers to take a measurement. Take three measurements and average the three. Record the results on paper. Because you're measuring tissue that compresses, it takes a fair amount of expertise to arrive at consistent results, so be sure to take several measurements for each site and average the three. Even lab technicians who have performed thousands of skinfold measurements take multiple measurements and average them. Step 4 Calculate a man's body fat. Assume that the total thicknesses of the nine skinfold sites is 96mm; divide them by the body weight of the subject (assuming a 190 pound male) = Multiply the result by The result would be 14 percent body fat: 96/190 = * 0.28 = 0.14 (14 percent body fat) Step 5 Measure the percent body fat for a woman. This is done in a similar manner as for men, with one exception: the calculation uses 0.30 instead of To make the example simple, let's assume the same total skinfold measurements of 96mm and the same body weight. The equation would look like the following: 96/190 = * 0.30 = (15.2 percent body fat) 6/4/2016 8