The unique design of the Xtenex lacing system resolves the problem of lace migration. Lace migration is the gradual movement of the shoe lace toward the forward bend of a shoe, which causes two main problems. Binding: a tightening & restricting pressure at the top of the shoe. It can lead to foot fatigue, pain, numbness & restriction of natural foot swelling.. The migration loosens the fit around the footwear’s metatarsal area, which causes increased slipping & reduction of forward foot stabilization. This can produce heat friction, which often leads to painful blisters.