According to The Old Farmer's Almanac 2000, a waist measurement of 35 inches or more in women and 41 inches or more in men—regardless of height—suggests a serious risk of weight-related health problems. Very muscular people often have a higher body-mass index because muscle weighs more than fat. One simple health-risk test is to pinch your side just above your waist. If you can pinch more than an inch, you are at risk of weight-related health problems. The amount of skin may be found using the formula: where height is in centimeters and weight is in kilograms. The result obtained is surface area measured in square meters. Weight is approximately proportional to height times height times height (i.e. your height cubed). Body-mass index is essentially a ratio of volume to surface area. The solid geometric figure with the greatest ratio of volume to surface area is the sphere.
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