The cardiovascular and exercise assessment protocols of the American College of Sports Medicine, ACSM, use weight-to-hip ratios to categorize your risk level for cardiovascular disease and safety at different exercise levels. Higher ratios are also indicative of hypertension, diabetes and coronary artery disease. Learning how to properly measure your waist and hip will ensure any categorization you base on this ratio meets ACSM standards. Waist-to-hip ratio is useful for the normal population; in some cases, however, this measurement has limitations.
To measure your waist properly, stand upright and relax your arms at your sides. Move your feet together and breathe normally while keeping your abdominal muscles relaxed. Find the narrowest area between your navel and the bottom of your sternum. Wrap a cloth measuring tape horizontally around your waist where it is narrowest. Record the measurement in centimeters. Repeat after resting for 30 to 60 seconds. The measurements should be no more than 5 millimeters apart. If the measurements are more than 5 millimeters apart, perform a third measurement. Take two measurements that are within 5 millimeters of each other, add them together, and divide the total by 2 to get your waist circumference.
To measure your hips properly, stand so you can see your side view in a mirror and spread your feet approximately 10 centimeters apart. Locate the level where your buttocks protrude the most. Wrap the measuring tape horizontally around your butt and hips at that level. Record the number in centimeters and relax for 30 to 60 seconds. Repeat the measurement. If the measurements are more than 5 millimeters apart, measure again. Add two measurements that are within 5 millimeters of each other and divide the sum by 2 to get your hip measurement.
Calculations and Evaluation
Your waist-to-hip ratio is simply your waist measurement divided by your hip measurement. For instance, if your waist is 81.4 centimeters, which is roughly 32 inches, and your hip measurement is 106.6 centimeters, or roughly 42 inches, the equation is 81.4 / 106.6 = 0.76. For women, a waist-to-hip ratio higher than 0.86 is considered dangerous or unhealthy. For men, a ratio higher than 0.95 is considered dangerous or unhealthy.
The waist-to-hip ratio does have limits. It should not be used to assess pregnant women because the waist circumference expands as the baby develops. Individuals who have recently had liposuction of the waist or hips should also be assessed using other measurements because the ratios will have been artificially manipulated. This measurement is not accurate if you have recently had a meal because the food and liquid in your stomach will cause your waist to expand and artificially increase its circumference.