 Excessive strain on the tendons and ligaments of the feet can result in fallen arches or flat feet.The muscles acting on the foot can be classified into extrinsic muscles, those originating on the anterior or posterior aspect of the lower leg, and intrinsic muscles, originating on the dorsal (top) or plantar (base) aspects of the foot.All muscles originating on the lower leg except the popliteus muscle are attached to the bones of the foot.