A method of manufacturing composite material parts is provided. A drive shaft passes through the housing and a compression element is coupled to the drive shaft between the low pressure chamber and the high pressure chamber. The first strap couples to the first frame member about an end portion thereof to temporarily attach the exercise device to a user. To minimize the encroachment of the scaled color-keyed regions into the scaled non-color-keyed regions of the scaled color-key image, the edges of the scaled color-key regions are sharpened by defining the color-keyed region as the region wherein each scaledfiltered color-key value exceeds a non-zero threshold value.