The subjects' legs were shoulder-width apart and their weight was shared equally. The measurer puts the tape measure behind the hip and measures the circumference of the thigh horizontally, which is the thigh circumference.

Comparing the measured girth values of the left and right thighs, we can see whether the muscles of the left and right thighs develop evenly. The thigh circumference is also called the maximum thigh circumference, not the middle thigh circumference.