Originally Posted by Jadebatdog
Yes, the scale simply said my body fat percentage which is 48.8% and my weight which was 242 or so. I guess based on that she could see that I have 117 pounds of fat and 126 pounds of lean, although I thought it was strange because there is more in my body then just muscle and fat such as water.
Actually, the measurement is "lean body mass" not muscle, which includes bones, water, etc.
I found a decent explanation
"Body impedance is measured when a small, safe electrical signal is passed through the body, carried by water and fluids. Impedance is greatest in fat tissue, which contains only 10-20% water, while fat-free mass, which contains 70-75% water, allows the signal to pass much more easily. By using the impedance measurements along with a person's height and weight, and body type (gender, age, fitness level), it is possible to calculate the percentage of body fat, fat-free mass, hydration level, and other body composition values. Conventional BIA normally uses underwater weighing as its method of reference.
Using BIA to estimate person's body fat assumes that the body is within normal hydration ranges. "