Plastic optical fiber (POF) wrapped around two steel posts is stretched by increasing the post separation. A nearly linear relationship between the strain of the POF segments between the posts and optical attenuation is reported. The primary cause of the attenuation is the radial compression of the POF in contact with the posts. The radial compression is approximated using contact stress theory. The cross-sectional area deformation caused by the radial compression is modeled as a fractional area loss. Optical power loss is shown to be nearly equal to the fractional area loss, since the POF cross-sectional irradiance is approximately uniform.